Slaying a greenhouse dragon

So, if you have followed the Climate Etc. threads, the numerous threads on this topic at Scienceofdoom, and read Pierrehumbert’s article, is anyone still unconvinced about the Tyndall gas effect and its role in maintaining planetary temperatures? I’ve read Slaying the Sky Dragon and originally intended a rubuttal, but it would be too overwhelming to attempt this and probably pointless.

I was hoping to put to rest any skeptical debate about the basic physics of gaseous infrared radiative transfer. There are plenty of things to be skeptical about, but IMO this isn’t one of them.

Well, my statement has riled the authors of Slaying the Sky Dragon. I have been involved in extensive email discussion with the authors plus an additional 10 or so other individuals (skeptics). Several of these individuals on John O’Sullivan’s email list actually agree with my assessment, even though they regard themselves as staunch AGW skeptics.

One of the authors, Claes Johnson, along with John O’Sullivan, expects a serious critique from the climate community. Johnson says he intends to submit his papers to a peer reviewed journal. I agreed to host a discussion on Johnson’s chapters at Climate Etc., provided that the publishers of Slaying the Sky Dragon would make Johnson’s chapters publicly available on their website (which they have).

Johnson’s first chapter is entitled “Climate Thermodynamics,” which presents an energy budget for the earth and its atmosphere that does not include infrared radiation. The second chapter is entitled “Computational Black Body Radiation,” which seeks to overturn the last 100 years of modern physics and concludes that “back radiation is unphysical.”

John O’Sullivan’s advert for the debate at Climate Etc. (note Monckton and Costella are in my “corner” in criticizing the book and Johnson’s chapters).

I suspect that many undergrad physics or atmospheric science majors at Georgia Tech could effectively refute these chapters. I’m opening up this discussion at Climate Etc. since

the Denizens seem to like threads on greenhouse physics

I’m hoping we can slay the greenhouse dragon that is trying to refute the Tyndall gas effect once and for all.

It will be interesting to see how this goes. Claes Johnson has said that he will participate in the discussion.

Note: this is a technical thread, please keep your comments focused on Johnson’s arguments, or other aspects of Slaying the Sky Dragon. General comments about the greenhouse effect should continue on the Pierrehumbert thread.

2,518 responses to “Slaying a greenhouse dragon”

It’s an interesting concept, that an atom cannot absorb (but only reflect) incoming EM at a cooler temp than its own blackbody emission temp at that instant. No idea if it’s true. My layman’s understanding of the thermodynamics constraint was just that it described net transfer, which must always be from hot to cold.

I have to agree with omnologos on this. By inferring that all those skeptical of the man-made global warming meme (some, like us, skeptical of the greenhouse gas theory, itself) are supposed to be seeking a unified front as if we are a political or military force is, frankly, absurd.
We prefer to leave ambitions to claim a consensus to the post-normal science green brigade; they appear to have abandoned the traditional tenets of the scientific method. Consensus is utterly meaningless- being proven right is the goal even when the so-called ‘consensus’ is adamant we are wrong.
The statement, “I suspect that many undergrad physics or atmospheric science majors at Georgia Tech could effectively refute these chapters” is so funny coming from someone who is “too busy” to do what she infers is such a basic task, herself.

Well, I mainly found it interesting that a number of people on your self selected email list were highly critical of the book and Johnson’s chapters. Your email list does not begin to reflect the broader range of skeptical opinions.

Judy, I intentionally invited to participate those who I knew to have contrary views . This is the whole point of debate isn’t it? Let’s see some actual analysis please rather than insults and hand waving so far displayed by those made uncomfortable by what the book presents.

I was positively surprised by the first chapter, which correspond to the mental model I have formed about GH effect, but I do not really see where it is in conflict with mainstream view nor why it is independent of infrared radiation. On the contrary, it explicitely agree with mainstream view, that is that TOA is variable in height and the higher the more GH gaz is present. The only thing it add is that lapse rate below TOA is related to thermodynamic and not radiation, and that lapse rate can vary with humidity and thus is a potential feedback (negative feedback). Up to here, I perfectly agree, appart that one should mention that it is an approximative model because all radiation does not happen a a precise TOA height, but that TOA is an average concept, the atmosphere is not perfectly IR opaque and then IR transparent, it is semi-transparent so radiation is a diffuse process and all radiation occuring at TOA is only a (usefull?) approximation.
At this point, the model does not allow to predict the change of T_ground when CO2 is doubled, what would be needed is the change in TOA from CO2 doubling, and the various H2O feedbacks (on TOA itself, and on lapse rate). Still, this model seems to me much more useful and closer to reality than pure radiative model with an IR opaque shell-like atmosphere concentrated at TOA, and the (negative) feedback of H2O on lapse rate seems perfectly valid (and not mentioned explicitely on previous GH accounts I have read).

This first chapter does not ring any physical alert bells though, so I guess reading the rest makes sense, and I am for now positively surprised by “Slaying…”…

oups, forgot to say: read the Pierrehumbert thread where I attempt to expose the mental model I built about GH effect. Done that only from the various GH threads here, at wuwt and rc, not from the “Slaying….” chapters….So u see why this first chapter was appealing to me :-)

ouch, started reading second chapter about blackbody…yikes, this one is definitely in crackpot territory, so “Slayer….” is a kind of mixed bag imho, if most chapter are long the first one, it is worthy, else (or if conclusion hold only if all chapters are true), then it will easily debunked…

Kai, the first chapter rests on the result of the 2nd chapter (they are both written by Claes Johnson), i.e. there is no back radiation and atmospheric infrared radiative transfer is not important in the earth’s energy balance. So if Ch 2 is crackpot, then Ch 1 is also.

Dr Curry,
To help the readers understand, please:
1. elaborate your definition of back radiation and your concept of it,
2. explain whats wrong with ” atmospheric infrared radiative transfer is not important in the earth’s energy balance”.

The Earth’s mass is so huge compared with atmospheric mass. The Earth’s IR energy emitted is so huge as compared with atmospheric absorption of IR energy. Will you care to do a comparison? Why is NASA’s radiation energy balance for K-12 incorrect?

Dr. Curry,
I admire your tactics of diverting your GT students’ attentions for avoiding direct answers to direct questions soon I found the Figure 1 model there is not a true representation of the atmosphere radiation transfer, namely, lack of the cloud radiation transfer and lack of layers direct radiation transfer to the Earth surface.

Its easy to make a generalized comment. I find generalised comments do increase misconceptions. Will you be more specific, such as list them out item by item, concept by concept, misconception by misconception, page by page? Doing it this way helps the readers understand your points of view.

Dr. Curry,
I am sorry you felt obliged to give so much space to the ‘Dragon’ book.
But if anything, it will unify skeptics by giving many something to agree on that fails as a skeptical case.
I see this book as sort of a left hand paranthesis to Hansen’s Venus-ization of Earth as a right hand paranthesis, expressing clear markers where wishful thinking has taken over.

Well yes, you admit to solar radiation and black body radiation. But your treatment in the first chapter completely omits atmospheric gases (and cloud) infrared radiative transfer (and includes that ludicrously incorrect diagram from more than 10 years ago that somehow continues to exist on a NASA web site).

Having said that Johnson is wrong, I’d like to point out that his first chapter on climate thermodynamics – emphasizing heat transport by convection and evaporation, but not including radiation from the atmosphere, is no more wrong than Pierrehumbert’s article which does the opposite – making the incorrect claim that the surface temperature can be determined by calculation that only includes radiation, ignoring convection and evaporation.

And yet of these two incorrect articles, Judith refers to one as “excellent” but says that the other could be refuted by undergraduates. I wonder if these same undergraduates could refute the Pierrehumbert article? I expect most could not, because the new generation of students are being brainwashed in the same way, for example by the GaTech course “EAS8803 – Atmospheric Radiative Transfer”. I note that the blurb for this course says that “Topics to be covered include the radiative balance at the surface”. I do hope that you have some students bright enough to realise that there is no radiative balance at the surface, and that one day this fact will dawn on those who design and teach the course.

Why NASA did not correct it and misled the general public for over 10 years with that incorrect diagram? Or NASA is incapable of understanding the subject of radiation? Or under the authority of James Hansen, no one in NASA dare to correct it?

This diagram apparently first appeared in a doc designed for K-12 education. The names Eric Barron (currently president of Florida State University) and John Theon were on the doc (back when theon was still employed at NASA and Barron was at Penn State, which places it in the mid 90’s). But I assume this diagram was drawn by a staff person, and Barron didn’t pay close attention. That is the only way I can explain this. Somehow John O’Sullivan spotted this (or at least publicized this). And it sits on a web site to the present day. In spite of my contacting several people about this. The bottom line is that there is too much form and not enough substance oversight on public communication documents (as opposed to satellite data quality issues, where there is a lot of oversight and checks and balance in place at NASA).

Over the 10 years, this diagram has misled the K-12 students, the teachers, the politicians and the world who visited the NASA site. This is a serious American educational flaw that NASA, Eric Barron and John Theon should be informed to correct the diagram or delete from the NASA website and owe the American Education and the world an apology.

If you have not asked them to correct it, please do as an educator at the Georgia Tech.

I’m not clear which diagram you are discussing here. If it is Fig 5 of Chapter 2 of Johnson then it does closely resemble Fig 7 of Kiehl and Trenberth 1997. If the latter was ‘ludicrously incorrect’ then it was still given pride of place 10 years later (with added colour but no other changes apart from the caption) in IPCC AR4 WG1 Chapter 1, p 96 (2007). But I thought Dr Curry was referring to Fig 4 of Ch 1 of Johnson, which is also attributed to NASA, but which differs from the Ch 2 version in not showing any downward long-wave radiation. Is that also derived from K & T?

Judy: You say that “I suspect that many undergrad physics or atmospheric science majors at Georgia Tech could effectively refute these chapters”.

I suggest that you actually try this as a take home exam for your students.
From your teaching they will understand that Kiehl-Trenberth is wrong
but maybe they will find something they think is right. Go ahead!

Apart from an over-indulgence in post-modern civility, the chapter on Climate Thermodynamics pursues the misconceptions underlying current AGW theory. A helpful touchstone for pdf files is a scan for the word equilibrium where used to describe what physical science calls steady states. I find three such instances in this chapter, all wrt the adiabatic lapse rate. Equilibrium states have no net fluxes of matter or energy entering or leaving. (Canonical ensembles allow fluctuations.) Equilibrium profiles are isothermal and the adiabat is not. Steady states require external fluxes to prevent them from relaxing to equilibria. The alert student should now be asking, how do I determine this flux needed to maintain an adiabatic profile?

With CO2 doubling, one typically calculates a 2% flux reduction and then presumes a 2% increase in the thermodynamic potential difference (1/T) is needed to restore the flux level. Thus, given a 65K tropospheric differential, 1.3K. An alternative interpretation is that adding CO2 increases the resistivity of the troposphere, just as traces of phosphorus disproportionately increase the resistivity of a copper wire. Thermodynamics asks, what change in potential is required to restore the original rate of dissipation of free energy? In high school we learned the expression E^2/R, albeit in a different guise. Ergo, only a 1% potential change now compensates a 2% resistivity change to restore energy balance.

When our student resolves the difference in these solutions, he should be able to answer his earlier question. Perhaps herein lies Sommerfeld’s dilemma – thermodynamics is not the intuitively obvious subject it may superficially appear. To paraphrase yet another quotation, ” …, and you’re no Arnold Sommerfeld.”

Is the presumption of a 2% change in (1/T) tied to a 2% change in flux found in textbooks, and generally accepted in the climate change literature?
If so, then the generally accepted value for climate sensitivity is a factor of 4 too large. The reason is that the Stefan-Boltzmann law says j is proportional to T^4. Taking the derivative of both sides with respect to T, and then dividing both sides by the Stefan-Boltzmann law, and rearranging shows that the % change in T will be 1/4 times the % change in flux. Because 1/T contains T^1, the % change in (1/T) will also be 1/4 times the % change in flux. You and all other knowledgeable bloggers are asked to comment on and make any corrections to my calculations found at https://judithcurry.com/2010/11/30/physics-of-the-atmospheric-greenhouse-effect posted on Feb. 7 at 7:44 pm.

Well, of course Johnson is wrong. It is perhaps instructive and useful to try to explain why. In the ‘blackbody’ chapter he seems to think that a warm body can warm a cooler one but not a warmer one. He says at one point (sadly no page numbers) that there is two-way propagation of waves, but only one-way propagation of energy. How does that work? Are there two types of EM wave, one transporting energy and one not?! We can also ask him this : an isolated backbody is radiating into a vacuum. Then a warmer body is brought in. How does the first body ‘know’ to stop radiating energy in that particular direction?

Later on he tries to use equations – but his equation (4) is just wrong. Where does this equation come from? What is u supposed to represent? Why is radiation given by the third time derivative of u?

The email debate of last week was the first geniune airing of the flawed Physics of AGW in all history. The fundamental flaws are explained in “OMG….Maximum CO2 Will Warm Will Warm Earth for 20 Milliseconds” posted at ClimateChangeDispatch.com and at the SlayingtheSkyDreaong.com website. Surprising that the truth was hidden in plain sight for so long. Since the show is now over, I felt it necessary to add one final comment “Climate Follies Encore” which explains the post 20 Millisecond exchanges. This has been the greatest education process, for the wisest among us, and we will now share.

My chapter includes over 100 pages of footnotes and is supported by 60 articles in archive and Canada Free Press. We share a glorious future of truth. My thanks to Judy for enduring my repeated, well meaning barbs for over a year now. (co-author of SSD)

To PaulM: You have not read and understood my argument: I present a differential equation modeling two-way wave propagation combined with
radiation and with a dissipative effect making the energy transfer one-way,
from higher to lower frequency. If you don’t like this equation, give me one you think is a better model. Just words is to diffuse to discuss.

Perhaps you should start by reading a standard text book on Radiation Heat Transfer and then move on to some papers (H C Hottel would be a good start) and learn about the subject rather than propose some wild theory? The fact of ‘backradiation’ has been well tested in many situations, furnaces, radiation shields for thermocouples etc., let’s see you apply your theory to such situations and see how it works?

Please define back radiation which confuses me even though I had written something about it. To me, back radiation is reflection from the back with wall or relective radiation. A thermocouple when placed at the center of a pipe gain heat from the flowing media as well as radiation directly from the wall concentrated at the thermocouple measured an erronous fluid temperature. With such a wall you get radiation concentration. Without a wall, the radiation is minmal.

Similar analogy for the greenhouse situation, greenhouse has glass or sheets of clear plastics to trap most IR, without this layer of wall, no trapping of IR and hence no greenhouse. It is obvious.

2 black bodies at different temperatures, they all emit IR with the resultant energy flow from the hotter to the colder in a free radiation condition. The colder can have an extremely small effect of slowing down cooling of the hotter unless a back wall from the colder reflect the radiation to other directions are reflected by the back wall.

I have not read Mr. Claes Johnson’s article about the radiation. I will assume he is mostly correct in a free field radiation as in most climate situations. There is no back radiation. Furnace, thermocouples etc cases are not free field radiation cases which involved walls of reflecting radiations. Radiation involves walls of reflection has back radiation.

Maybe you could explain what makes the old one and the “new” one “ludicrously incorrect”,
that might help in discussing what the “slayers” are showing, saying, suggesting, and raising for discusion.
Heck, we might even get to a better understanding of where the science actually is at present.

PS to PaulM: I start from the same equation as Planck did 100 years ago, but combine with finite precision computation instead of freely invented ad hoc
statistics. Statistics is not physics, just imagination, and physical particles have little imagination.

“Statistics is not physics, just imagination, and physical particles have little imagination”.
How dismiss 200 years of thermodynamics and physical statistics, with the only clue of a single metaphor: the “not-thinking” particle. Funny (what about: Einstein debunked, there is no light speed maximum: photons don’t care about cops and driving speed limits ?).

Read the second chapter – it’s goofy, not physics. The initial clain to get rid of wave particle duality pretty much floored me, since this aspect has been very well experimentally shown. To accept this assertion means ignoring what you can see with your own eyes (and instrumentation) in a laboratory. A fatal flaw is confusing net energy flow with absolute energy flow – this is in the black body discussion. To say that a colder black body can’t radiate to a warmer black body (he calls this “back radiation”) is beyond ridiculous.

Basically, he presents a circular argument without proving his ridiculous premise, throws a bunch of jibberish (maybe not jibberish, but I don’t call it physics) in the middle to make it all seem scientific, and then returns to his unproven assertion that a colder body doesn’t have black body radiation in the direction of a warmer body. Thus, besides claiming no one knows the nature of a photon (as part of an argument against the traditional treatment of blackbody radiation – yet single photon experiments have been run for decades) , he negates the Superposition Principle and relies on some mysterious instantaneous knowledge existing in one body about the temperature and direction of all other bodies in the universe. I think the spook guys would love to have this type of instantaneous directional communication device in their hands.

Just to make it more clear, suppose you have two black bodies at different temperatures facing each other, with a shutter over each blocking all radiation. Remove the shutter in front of the colder body an very short time before removing the shutter in front of the hotter one. Then initially radiation would flow from the colder one toward the hotter one, and then reverse direction when the second shutter is opened.

The question is, can a cold body make a warm body hotter? Everything with mass and a temperature radiates. Who disputes that?

Imagine a hot body (with an internal or external heat source) and a passive body floating in the vacuum of space. Can the passive body make the hot body hotter? Imagine the passive body gets closer to the hotter…it will absorb more radiation, right? It will get warmer. If there was such a thing as back-radiation heating, then the hot body gets more of it back. Then the bodies get so close together…that they touch. Now the radiation effect is greatly magnified (whatever radiation can do, conduction does much better).
Does the hot body, at any time during this process, ever get hotter?
Radiation from a passive source cannot make a hot body hotter.

It certainly can, put a thermocouple in a flame and you’ll measure a certain temperature which is lower than the surrounding flame because of conductive losses down the wire and radiative losses to the surroundings. Surround the ThC with a silica tube and the temperature measured will increase due to radiation from the cooler tube.
Check out ‘Suction Pyrometers’:http://www.combustion-centre.ifrf.net/requipment/temperature-heat/suction_pyrometer.html

I can’t tell if you’re kidding, Phil.
Transport your experiment into space so we can focus only on radiation effects. Then replace the flame heat source with a resistive one so it will work in a vacuum. Now, tell me how the passive thermocouple can increase the temperature of the heated body. The only thing it can do is cool the heated body…at various rates and with varying degrees of coupling, sure. But, under no condition can it make the heated body hotter. The passive body is never a source of heating for the source. Never.
Now, what does that tell you about Trenberth and Keihl’s energy balance schematic? The earth’s surface is heated by back radiation from passive CO2 and water vapor?

The topic is radiation, Phil, the supposed mechanism for global warming caused by increasing CO2 in our atmosphere. You love to talk about conduction and convection as if I don’t understand these concepts, but that is a hand-waving distraction. Focus, Phil. We’re talking about radiation…and how a passive body can heat a body with a heat source. I know how a passive body can cool a hot body…let us count the ways. Your GHG theory depends on passive materials heating hot materials.
What are you going to do with radiation, Phil. Store it? Delay its transit time to space? You can reflect it, diffuse it, deflect it or focus it. You can’t store it or “back radiate” it to make a warm surface warmer.

”
You can’t store it or “back radiate” it to make a warm surface warmer
”

It reradiates in all directions – the use of “back” is arbitrary and capricious, and assumes the location of another black body is somehow important. To be correct in what you say, it would have to stop radiating in a particular direction just because there is a black body in that direction – that’s ridiculous.

“radiative losses to the surroundings. Surround the ThC with a silica tube and the temperature measured will increase due to radiation from the cooler tube.”
Missed this did you?
And this, the first sentences in the cited reference:
“When a bare thermocouple is introduced into a flame for the measurement of gas temperature, errors arise due to the radiative exchange between the thermocouple and its surroundings. In the standard suction pyrometers a platinum-rhodium thermocouple, protected from chemical attack by a sintered alumina sheath, is surrounded by two concentric radiation shields.”
Yes Ken we are talking about radiation but unfortunately you don’t understand it.

The atmosphere is in thermodynamic equilibrium. There are slight variations which are caused by certain cyclical processes which the proponents of AGW mostly refuse to accept.

CO2 concentration is not one of them. John Tyndall did not prove a damn thing about CO2 absorption. His equipment was far too primitive to distinguish between absorption, reflection, refraction, diffusion, scattering or anything else. He incorrectly concluded that all energy missing between the source and the pile in his half baked experiments had been absorbed by CO2. Above all he ignored Kirchhoff’s law.

The conservation of energy falsifies the “greenhouse effect” because as per Kirchhoff’s law that which absorbs, equally emits. This fact is absent from Tyndall’s ramblings and exposes him for what he was.

Nothing traps in heat, quote:

“All matter–animate or inanimate, liquid, solid, or gas–constantly exchanges thermal energy in the form of electromagnetic radiation with its surroundings. If there is a temperature difference between the object in question and its surroundings, there will be a net energy transfer in the form of heat; a colder object will be warmed at the expense of its surroundings, a warmer object cooled. And if the object in question is at the same temperature as its surrounding, the net radiation energy exchange will be zero.”

“In either case, the characteristic spectrum of the radiation depends on the object and its surroundings’ absolute temperatures. The topic of radiation thermometry for example, or more generally, non-contact temperature measurement, involves taking advantage of this radiation dependence on temperature to measure the temperature of objects and masses without the need for direct contact.”

“The development of the mathematical relationships to describe radiation were a major step in the development of modern radiation thermometry theory. The ability to quantify radiant energy comes, appropriately enough, from Planck’s quantum theory.”

According to Kirchhoff’s Law any substance which absorbs energy will equally emit that energy. CO2 has a lower specific heat capacity to O2 and N2. The atmosphere which is 99% N2 and O2 is in relative equilibrium. Therefore adding more CO2 at trace amounts to the atmosphere will simply force the CO2, with its lower specific heat capacity, into equilibrium with the rest of the atmosphere. The higher the concentration of CO2 the lower the overall atmospheric temperature will become.

AGW theory requires that we suspend our knowledge of this obvious fact and accept that it is the 0.0385% CO2 which forces the other 99% of the atmosphere into equilibrium with itself.

It is the same logic as claiming that by taking a pee in the ocean, you have warmed the ocean. When in fact your pee has been chilled by the ocean. It’s called semantics.

It is interesting that Judith has played the appeal to authority card. It is also interesting that those who appeal to the authority of Tyndall and the RS (7GT/1Gt human v’s natural CO2!) fail to acknowledge that they are relying on primitive out of date 150 year old “science” which has not even been critically re-examined.

Anyone who quotes John Tyndall as the man who proved the “physics” of the “greenhouse effect” displays nothing short of sheer ignorance. It is the ultimate in the bogus appeal to authority. John Tyndall was fool and a fraud. Above all he was an insider at the Royal Society. Tyndall’s experiments have as much value as Sir Paul Nurse’s implication in his recent Horizon “program” that natural processes account for 1 Gt CO2 while humans account for 7 Gt CO2, i.e. NONE.

So can we quickly dispense with the pseudo science of John Tyndall and get back to reality? That appeal to authority was for yesterday’s people, those who had faith in the integrity of science, scientists and trust in the Royal Society.

Those people are long gone. (Last seen heading south on highway 51 with Trust in the passenger seat and Faith at the wheel!)

You can see why I am personally not taking this on in any detail, it is just endless. You incorrectly state Kichoff’s Law. αλ = ελ, where Lambda should be a subscript. it says that at a particular wavelength, the fractional absorptivity equals the fractional emissivity, where the fractional part is relative to the intensity of black body radiation at that wavelength. So if an oxygen molecule at temperature 200K receives a bunch of solar radiation in the ultraviolet bands, it will also emit in the ultraviolet bands, but because the oxygen molecule is relatively cold, there is almost no actual energy emitted by an oxygen molecule with temperature of 200K. Your next sentence is a mistaken interpretation of very basic elements of the kinetic theory of gases. And on and on . . .

My point in not rebutting all this personally is that I would need to spend an hour on each incorrect sentence to try to educate people that don’t already understand this. Roy Spencer and scienceofdoom have already tried. And there are hundreds of such sentences to rebuke.

“My point in not rebutting all this personally is that I would need to spend an hour on each incorrect sentence to try to educate people that don’t already understand this. Roy Spencer and scienceofdoom have already tried. And there are hundreds of such sentences to rebuke.”

That’s an equilibrium condition, Will. Given that we’ve been doubling the amount of CO2 we add to the atmosphere every three or four decades for the past century or more, we are nowhere near equilibrium. Nor will we be until (a) we hold constant the amount of CO2 we add each year and (b) nature catches up. Expect (b) to happen roughly three decades after (a). But don’t expect (a) to happen until we can no longer afford fossil fuel. And at that point (a) won’t happen anyway since our CO2 production will decline thereafter rather than holding steady.

David Archer believes things will remain hot thereafter. I disagree: I believe that after we stop emitting CO2 the temperature will plummet even faster than it has been rising due to the way equilibrium works. Conceivably by 2150 we’ll be in a Younger Dryas type ice age, though at that point we’ll surely have figured out some way of preventing that.

To Harold: Yes physics is very goofy, in particular particle statistics physics.
I start from the same wave equation as Planck and use a finite precision dissipative effect instead of jibberishy statistics. So what I do is less spooky
than what you hint at. It is remarkable that in a discussion about the “greenhouse effect” physicists have nothing to say. To me it is a physical phenomenon that physicists should be able to grasp, but it seems they don’t.

I guess you didn’t get it. I’m a trained Physicist, now retired. I was pretty sure I just said something about the greenhouse effect, and particularly pointed how a simple thought experiment shows how wrong your theory is. I don’t intend to try to convince you, but my thought experiment should convince almost any reasonable idiot your theory is wrong.

I don’t use different standards for either side of AGW. I have fairly rigorous standards,, which you have failed, and most ot the AGW papers also fail my standards. Sloppy work on the AGW’s crowd’s part doesn’t excuse sloppy work on the anti-AGW’s side. As for dragging Tyndall into the discussion and how the physics hasn’t been looked at, try reading some of Dr. Earl W. McDaniel’s and others’ books from decades ago on details of atmospheric excitation and radiation.

Dr. Curry – FYI, Dr. McDaniel taught Physics at Georgia Tech, and had a great sense of humor.

Claes
This is a very interesting thread. If it wouldn’t be too much trouble, would you mind using the ‘reply’ button to respond to comments. It can be found next to the name and date/time of the person that you are replying to. It positions your response at the correct point in the blog and makes it easier for us lurkers to follow the argument. Many thanks.

Having read just the first couple pages of the second chapter, I know this argument is going to ‘creative’.

The first argument is rather interesting. Blackbody radiators absorb all frequencies of light (definition of ‘black’), but only emit radiation with a specific spectrum determined by the body’s temperature. I think that’s fairly standard physics canon.

But the train gets off the tracks pretty quickly after that. The author makes the statement,

‘The net result is that warmer blackbody can heat a colder blackbody, but not the other way around.’

which is obviously wrong.

But why?

Before this gem of a statement, the author goes through several analogies (which aren’t as informative as equations) proving to himself that only high frequency light that is not being emitted by the blackbody can increase the temperature of the body. This energy is absorbed, then Stokes shifted to lower energy by coupling to internal modes of whatever form of matter we’re discussing. In molecules, mostly vibrational and rotational degrees of freedom, along with intermolecular collision, play this role.

The implied converse of this statement is that energy absorbed by the warmer blackbody from the colder blackbody is not outside of the frequency range of the warmer blackbody’s spectrum, therefore it doesn’t add heat and doesn’t increase the temperature!

Brilliant!

The question then becomes, if we are talking about blackbodies that absorb ALL frequencies of light, what happens to the energy in the lower frequencies absorbed by the warmer blackbody? Surely there is energy in those photons/waves. Because the warmer blackbody is, in fact, a blackbody, it MUST be absorbing those lower frequencies. What happens to that energy?

I think most of us know that according to the conservation of energy, those lower frequencies absorbed by the warmer blackbody increase the temperature of that blackbody, even though the radiation was emitted by a colder blackbody. Kirchoff’s law is the mathematical manifestation of this fact. The emissivity of the blackbody in thermal equilibrium equals its absorptivity. Therefore, the thermal equilibrium of a blackbody can be shifted by changing its absorptivity in ANY SPECTRAL REGION, not just the high frequency region. This can be accomplished by increasing the inward flux of low frequency radiation due a nearby colder blackbody, as is the case with atmospheric greenhouse gases in the case of climate.

So, I don’t doubt that the author’s math and equations are correct. Unfortunately for him, it’s the interpretation of those equations, along the lines of high pass filters and classrooms, that is flawed and ultimately leads to the incorrect conclusion that the greenhouse gas can’t exist. Not even that it doesn’t exist, but that it can’t. It’s brilliant in its simplicity, really.

I would like to see this author handle the fact that we clearly observe a completely isotropic cosmic microwave background surrounding everything corresponding to a 4K collection of intra-solar and inter-stellar gases. I think that fact is fairly irrefutable proof that this guy is totally wrong.

Moreover, why are we continuing to clamor to convince people like this that they are incorrect. Anyone who put enough time into convincing themselves of this type of theory after many, many attempts of others to ‘disprove’ them is not going to be swayed by observational evidence, proof of principle experiments or even reason. It’s better to not give their theories credence by taking the time to ‘debunk’ them.

“Surely there is energy in those photons/waves. Because the warmer blackbody is, in fact, a blackbody, it MUST be absorbing those lower frequencies. What happens to that energy?”

Take a glass of water at 99 C and surround it with a dozen glasses of water, all also at 99 C. Does the water in the glass in the center get warmer? Does it cool off more slowly than it would if the other glasses were not present?

The net transfer of energy between the 99C glasses of water will be zero but all will be radiating energy at a rate appropriate for a single glass of 99C water. Again, all radiating but net transfer zero.

As for cool down, yes the central glass will cool slower. I suppose you could say that the other glasses are insulating it. What is happening mechanically is that the outer glasses are exposed to a cooler room so the net energy flow between them results in heat loss to the room. The inner glass then is exchanging energy with an incrementally cooler glass of water so it experiences an incremental net loss of energy. Until final equilibrium is achieved, the inner glass will remain warmer than the outer glasses and the outer glasses will remain warmer than the room.

Wow, this is really simple physics. I’m not a all sure how this can be so hard to follow.

In the water glass case, there is no steady energy input to the center glass of water so it will loose energy to the environment. The surrounding glasses increase the time that it takes to cool by radiating heat ‘back’ to it as they also cool by radiating their energy.

To increase the temperature of an warmer object by a cooler object, the warmer object must have an continuing energy input that must be dissipated. In that case, the presence of the cooler object near it radiating part of its energy toward the warmer object results in that energy being added to the total that the warmer object must dissipate. The temperature of the warmer object must increase again to radiate that somewhat larger total energy input.

Of course, if you insist there is no such thing as a photon or that two streams of photons cannot pass each other traveling in opposite directions, we probably will never be on the same ‘wavelength’. I’ve spent my life around electronics, radio, and nuclear physics. Maxwell’s equations rock for many aspects of electronics and radio but they are just very handy tools. Because Maxewell’s math works a good share of the time does not mean it defines reality. It is not very useful for use when counting gammas to determine the activity level of a radioactive source. Calculations based upon photons and nuclear interactions are the tools that work there. You should use the tool that suits the job at hand. I believe the photon view is the correct one for radiated energy discussions.

This is basic physics and basic engineering stuff. However, do not take this to mean that I believe doubling of the atmospheric CO2 is going to be a big problem. I don’t. I just prefer simple physics not be twisted to make a point.

Could you have picked a more complicated example, if you’re being rhetorical?

Dr. Curry’s more creative students will no doubt be asking about partial gas pressure, room temperature, convection, conductivity, where the lights are in the room, and will you refill the glasses as evaporation causes volume change, to start with. ;)

A glass ingot at 99 C, I could understand.

Especially if you included conditions like, “in a closed system initially at STP,” and “surrounded in all directions with no significant gaps,” and “all ingots behave as uniform spherical black bodies,” etc.

Does the water in the glass at the center get warmer? Unlikely, though Dr. Curry’s students could contrive extrinsic conditions to make it so, I am sure.

Does it cool more slowly? Likely, for most sets of extrinsic conditions, I think Dr. Curry’s able students will find.

More to the point, could you expand on your point, please, as it elludes me. (Though I’m sure Dr. Curry’s students would be able to explain it to me.)

We are using language of ‘external energy sources’ versus the system of interest, the surface of the earth in most of this discussion.

In this case, the outer glasses ARE an energy source for the central glass. They just happen to be at the same temperature as the central glass, in stark contrast with the earth-like situation in which the sun has a dramatically different temperature from the earth.

So let’s a assume the ‘other’ glasses are in a circle around the central glass and that the glasses can only emit energy out into the plane that contains all the glasses, for simplicity. Being all at 99 C, each glass will have some the same emissivity and emit the same spectrum. It is very likely that each glass can absorb most, if not all, of the energy emitted by the other glasses.

Now, to me, there seems to be two parameters that matter the most. 1) the temperature of the surrounding air and 2) the distance of the 12 ‘other’ glasses from the central glass. The temperature difference between each glass of water and the surrounding air will determine the difference in the energy absorbed by the central glass and the energy that it gives off due to the air by conduction. The distance between the 12 ‘other’ glasses will determine what percentage of the emitted energy from those glasses can be absorbed by the central glass. The closer the ‘other’ glasses are to the central glass, the more of the emitted energy the central glass can absorb. The further away, the smaller the percentage of energy that can be absorbed.

There *should* could be an air temp and distance from the ‘other’ glasses at which the central glass is taking in more energy from the surrounding air than it is giving off. In such a case, the central glass would increase in temperature as per the conservation of energy.

There are a number of glasses at the same temperature
“Being all at 99 C, each glass ”
The zeroth law of thermodynamics may be stated as follows:
If two thermodynamic systems are each in thermal equilibrium with a third system, then they are in thermal equilibrium with each other.
In the early days this was assumed but later questioned.
It had to be experimentally determined and since we already had Laws 1,2 and 3 it was called the zeroth.
Perhaps you are thinking about law 3 which is about absolute zoro

Zeroeth law well-established, a black body among bodies of equal temperature will not increase in temperature, though this says nothing of how quickly each will lose temperature or in what pattern.

If the air were above the temperature of the glasses, or if there were certain complex salts that underwent a physical change in solution in the central glass, if it contained fissile materials in high enough concentrations, if exothermic chemical changes happened in the ‘water’, if the air pressure were suddenly increased compressing tiny soda bubbles (or at 99C, nearly boiling so water vapor bubbles), if the glass were in an atmosphere of pure reactive metal particulate suspension (potassium, say), if there were a series of lasers deflected toward the central glass, or electric currents, or sound waves.. there are all sorts of extrinsic conditions that might raise the temperature of the central glass.

Which, as I said, a complex example.. and I still don’t follow the point of it originally being posted.

How about debunking quickly this way – two black bodies at different temperatures separated by a perfect reflector. With the reflector in place, heat travels from each black body, bounces off the reflector, and returns to the originating black body. Under the theory that was proposed in chapter2, when the mirror is removed, the heat from the cooler black body must still return to the cooler black body – it has to act as if there is still a reflector in place, but not so for the hotter black body. A ridiculous result. Bad physics…

before quantum physics and the idea that a photon was an actual particle there was wave physics that was, and still is, experimentally proven. Those physics experiments described scattering, reflection, interference, and cancellation. Why would this section of physics suddenly become null just because you apparently have forgotten it?

There are several possible explanations of why a cooler body would not heat a warmer body contained in this PROVEN area of physics and which are contained in the correct energy equations that give a NET energy flow.

That’s all I am asking of the cold object heating, or slowing the cooling of, the warm object by radiation. Empirical data.

One of the thought experiments I really like is the one where the heated object is surrounded by a cooler sphere which is thermostatically controlled. My imagination tells me that the radiation from the sphere is cancelled by the radiation from the heater leaving the net to be drawn off by the cooling system of the sphere with nary an effect on the heater itself.

I am told that this cool sphere will actually heat the heater. If the heater is made hotter by the cooler sphere, its radiation should be elevated measurably. If it isn’t measurable I really don’t care with respect to the climate disagreements.

But then why were you bringing up data and thought experiments in a discussion of wave equations, again?

I’m not sure I follow the analogy built into your thought experiment. Which is the thermostat? Which the air conditioner?

Help me with my own thought experiment:

There is a mall full of inventory that is replenished through another channel, with customers entering and leaving all the time through multiple sets of doors. The doors are designed to allow customers in without hindrance, but to slow some customers on the way out by redirecting them randomly through the mall (the mall hopes to increase sales this way). There’s a ‘sellostat’ set by the mall manager designed to set how much the doors slow outbound customers, but the manager’s salary is set by sales figures, and every day he gets greedier.

Can you see where my thought experiment is going, and maybe suggest improvements?

I like your idea about using a strip mall rather than doors. Much clearer, and suggests better parallels.

So, strip mall manager welcomes all buyers to his locale, and takes some steps (advertising posters facing people as they walk away from the strip mall, principally, but also shills who block the way out and chat up secret sales, and the smell of food from the strip mall’s food vendors) to hinder buyers as they leave.

At first, the manager sets out only small hindrances, but he believes that they work because the theory of advertising tells him so, and his mall sells more and more as he puts more hindrances up, and he sees no reason to stop putting up hindrances since he’s rewarded by profit. He’s so rewarded by profit, he pays off the local officials to allow him to put up more posters, and muscles out any competing shills trying to get buyers to leave for their strip malls up the street.

So, do you think the mall will be more crowded, the more the manager hinders buyers from leaving?

I wouldn’t say test so much as measure. It would seem that climate science, and maybe other fields, agree that there is backradiation and that either it slows cooling of the hotter body or heats it. I want at least one experiment, preferably several differing ones, that quantifies that relationship.

If it slows cooling, by how much. If it heats the body, by how much. Does there appear to be conditions that increase or decrease the effect we need to research more…

Why am I so adamant about real experiments? Because thought experiments are limited to the variables that we put into the experiment, you know, just like models. If we do not know about it or do not know it well enough to get a reasonable ball park figure, or cannot convert it to mathematics at a resolution that is useable, we have no way of knowing whether the results of our thought experiment is valid.

The world has a reality that we need to include and we do not know all that reality. Look at the empirical experiments that detail an effect very well, yet, we do not see the result of the effect generally in reality due to offsetting effects.

I will grant that there needs to be a lot of thought put into designing the experiments for these same reasons and there is where we find a good use for thought experiments. If we allow contamination the physical experiment will not be giving us results useful for the original purpose. Thought experiments can help us design the experiment to try and exclude contamination so we have a higher certainty of measuring what we think we are measuring.

I’m aware of multiple real measurements cited in this topic and elsewhere on this blog using advanced and proven equipment for decades.

I’m aware of multiple real experiments cited in this topic and elsewhere on this blog and in countless other sources.

On its face, the phenomenon of reflected radiation is so everyday commonplace that it would take extremely strong evidence, and with the addition of so much experimental proof, much better rebuttal than has yet been offered on these pages, to credit your words, “I want at least one experiment..” as anything but flat-out, and excuse me for being blunt, lie.

when did Backradiation become REFLECTED radiation?? This is something I definitely missed along with 99.99% of papers and work I have never read that are obviously inexistence in spite of my ignorance.

Please note, I am NOT trying to claim there isn’t literature, only that I am extremely limited in my exposure to the literature and reality.

You get the distinction between reflected radiation and back radiation?

Good.

Means you have an advanced and subtle grasp of the topic, and should be able to handle the things talked about in the blog by people who do serious measurement, experimentation, analyses and interpretation of these things for a living. (Which would be not me.)

I frankly don’t believe we are going to get to widely accepted experimental results along the lines of your suggestion any time soon, unless someone builds a pair of hermetically-sealed IR-transparent domes the size of Nebraska and experiments with changing their CO2 concentrations repeatedly under differing conditions of sunlight.

Too much room for waffle, and too much brute force logic. And even then, questions of applicability will bedevil us.

What we need is a guy with a teacup and some milk, and the ability to clearly explain so anyone can understand why the milk particulates suspended in it move.. erm, sorry. Wrong experiment. But you get my drift?

Photon? Why did you switch frames? I said heat, nothing about photons – I’m using a classical EM frame. Maybe you thought I was talking about photons, since the waves would have to suddenly turn around and return to their source under the proposed theory, which doesn’t make sense to you. That’s my point, the proposed theory doesn’t make physical sense.

OK, back to waves. The classical wave experiments show that waves can interfere, cancel, and augment (sorry for the layman’s terminology). Interference partially cancels or deflects, cancellation negates and augmentation adds. What happens to the energy Harold??

This has been shown to happen in experiments. Doesn’t it happen out there in the atmosphere? The thought experiment is that 2 bodies are radiating against each other. The colder body will be radiating at a lower energy peak, but the warmer body will be radiating at that wavelength also. Why won’t the waves at the same frequencies cancel or interfere?

At the quantum level I am even less adept, but, I understand that the particles need to have a correct energy state to absorb energy. What happens if the bodies do not have the correct open energy state to absorb the wave/photon carrying the energy? Won’t it be deflected/reflected instead? Isn’t this a more reasonable explanation of what we see in the atmosphere between GHG’s and the surface and each other for that matter?

Finally you suggested the wave would HAVE TO RETURN TO ITS SOURCE. . The wave would be deflected in another direction, although it would seem that it could be deflected back to the originating body.

What amazes me is that there is all this partially understood and misunderstood knowledge being tossed around. Yeah, kinda like me.

kuhnkat, reference your comment about e/m waves from several sources interacting with each other, maybe you should take intensity and phase (and polarisation?) into consideration too. It may help to move your though experiment on if you gave some consideration to a practical experiment carried out around 1800 by English scientist Thomas Young described in “Instruction Manual and Experiment Guide .. ADVANCED OPTICS
SYSTEM .. Experiment 4: The Wave Nature Of Light (http://www.fceia.unr.edu.ar/fisicaexperimentalIV/Pasco/Advanced%20optics%20system.pdf). Alternatively you could set up youjr own experiment using a candle and some card board sheets with slits cut in them (http://philmintz.tripod.com/Optics/page3.html).

If you’re interested, this interaction of e/m waves from a single source taking different routes to a common destination can present a surprising problem for Line-of-Site (LoS) radio communications links. Although the optical path from transmitting to receiving aerial may be unobstructed, the radio signal can be reduced (even to zero) as a result of cancellation of the signal travelling over several different paths (http://home.comcast.net/~dnessett/quietbird/HCJB.pdf).

I’m sure that Joel, the thread’s resident expert in all things to do with theoretical physics, can explain it all in simple terms far better than I. He must do it all of the time when lecturing to his RIT students.

Pete, to be honest, I find kuhnkat’s posts quite painful to read. He understands just enough about the existence of interference to be led astray into a variety of completely wacky conclusions.

First of all, interference occurs in only a very carefully prescribed set of circumstances. The light has to be of the same wavelength and to be “coherent”, which means that the waves are in lock-step with each other. Also, the geometry matters. Waves traveling in opposite directions (even assuming the coherence and all) don’t cancel each other out except at very specific locations separated by distances of half of wavelength, which means on the order of microns for what we are talking about. In between, they add together constructively. The result is a standing wave, such as is seen on a guitar string.

So, I really don’t see anything useful coming out of kuhnkat’s ramblings. They are just an attempt to turn the nonsense that we know Claes and the other Slayers are spewing into something intelligible. But, you can’t produce sense from nonsense by adding more nonsense.

Hi Joel,. I felt confident that a top lecturer like you woujld be able to present a compexy subject like e/m wave interactions in a simple manner. Well done, but can you please try to avoid unusual words like “coherent” and concepts like “standing waves” which might confuse us simple lay people.

The problem was, Joel, that Ridley turned to his library to look it up. But he couldn’t find either “coherent” and “standing waves” in his dog-eared copies of The Elders of Zion and Mein Kampf. So it’s good that you’ve given him links to look the terms up.

The other problem is, he won’t. Like Kuhnkat, Ridley uses ignorance as a war club to bludgeon his enemies.

Pete also prefers using his time and bandwidth to search for Holocaust deniers, Neo-Nazis, and Jihadists like Daniel E. Michael to quote. (Did you READ the Michael letter Ridley quoted yesterday that ends with “Death to America!!!”)

As the earth emits a relatively continuous band it emits the same wavelengths that are emitted by the GHG’s. While I readily agree that the amount of interaction is probably quite small, if we toss out enough minimal influences we make other amounts larger. (one of many issues with models)

How about an actual experiment to measure the backradiation effect. Something like a tube with earth at one end and a short wave source at the other. Use at least two runs, one with atmospheric gasses with no GHGs and one with GHGs computed to give the actual backradiation of a column in the open atmosphere. Measuring how fast the earth is warmed with and without GHGs should give a rough idea of how much the backradiation effect is. Or, has this been done and can you point me to the paper?? Simply shining IR through a tube of co2 tells us little about the effects of the radiation emitted by that co2 or h2o or ch4… on the ground. For the truly anal we could use differing types of material such as granite, dirt, wet dirt, loam, sand… to see how the effect is modified if there are measureable differences.

Actually a third run with close to a vacuum would be good to show that there is no difference between non-GHGs and a vacuum insofar as the rate of warming of the surface. That is, there is negligible backradiation from non-GHGs matching their negligible absorption.

This is the type of straightforward experiment that MIGHT convince some sceptics and deniers that there really is a measurable, significant in relation to the earth system, increase in warming speed. It should be able to clarify which of the ideas of no effect, slows radiation from the earth, or warms the earth is correct. I would note that some significant warmists apparently believe there is a real warming. An actual series of experiments should be able to sort this mess out!!

It is really silly to have all these conflicting discussions over the number of angels that can dance on the head of a pin when we should be counting them with electron microscopes or other detectors. (well I guess there is the issue of finding the pin they are dancing on or luring them to our dance)

Kuhnkat: I don’t even understand your experiment…and I don’t really see why scientists should waste their time running it.

For one thing, the basic physics of the radiative transfer in the atmosphere and specifically radiative forcing of CO2 is well-accepted and well-tested science by everyone who has even a small modicum of respect within the scientific community (e.g., Roy Spencer and Richard Lindzen accept it). So, the issue comes down to feedbacks and that is not something that can be settled by such a simplistic experiment.

For another, I am under no illusions that we can ever convince “skeptics” who doubt such basic tenets of science to become AGW believers. Such people are like Young Earth Creationists: they don’t disbelieve AGW because they doubt the science; rather they believe any bogus nonsense attacks on the science because they are ideologically opposed to the actions that follow from addressing AGW. If you guys can’t even comprehend and accept basic science about which there is no serious controversy whatsoever and instead believe nonsense, how am I ever to convince you on the issue of feedbacks and climate sensitivity, which actually require weighing the balance of the evidence? It is like telling me that if I can only get a Young Earth creationist to abandon the belief that the earth is only 6000 years old, he will actually fully accept evolutionary theory…Ain’t gonna happen!

Hi Joel, I agree with your comment (yesterday at 9:09 pm) about the heat retaining effect of water vapour and some trace atmospheric gases preventing some of the IR energy that is emitted by the earth from radiating back out unobstructed (AKA the Greenhouse Effect) and that humans adding a tiny amount of CO2 could result in a small (beneficial?) rise in temperature. Ias you say there are not many respected or knowledgeable scientists who consider otherwise.

On the other hand I’ll be very very surprised if you can provide a sound analysis of your own that convinces true sceptics that the balance of evidence indicates that a global climate catastrophe looms as a result of our continuing use of fossil fuels.

Rest assured that the use of fossil fuels will continue for many many decades yet and all of the scare-mongering by the power hungry, the UN, the politicians and the environmental activists will not change that.

I still haven’t seen your refutation of the analysis carried out by Roger Taguchi showing that the feedback effect is negligible. Was it too hard for you? OK, here a simple question. If positive feedback due to increased water vapour arising from a slight increase in global temperature due to our use of fossil fuels is able to cause a global climate catastrophe in the next 90 years why didn’t such a disaster happen during the Roman warming or during the MWP? I’m sure that you can explain that in simple enough terms for lay people like me to understand, but please don’t try to argue that the rate of warming now is far greater than ever experienced during the past 300M years or that Mann was correct and there was no such thing as the MWP.

the experiment is to see how fast the material warms with and without ghg’s in the atmosphere giving an empirical figure for the effect of backradiation in a carefully controlled experiment.

Why is this important? Because deniers like me say there is none. Luke-Warmers and warmers believe in varying amounts of slowing of the surface cooling, and some alarmists say the backradiation actually raises the temperature of the material above the level that the short wave can make it. Even if everyone suddenly went sane and decided there was only a reduction in the rate of cooling (faster warming also) it would be good to actually quantify by empirical experiment exactly what the magnitude of the effect is.

You say:

“the basic physics of the radiative transfer in the atmosphere and specifically radiative forcing of CO2 is well-accepted and well-tested science by everyone who has even a small modicum of respect within the scientific community”

Yet, that statement says NOTHING about the magnitude of the effect on the earth itself. I am sure you agree that different materials would react differently even if your theory is correct. Being able to put constraints on the effect in the models would be a real contribution outside of just making some people happy that their position was proven.

The Climate Science community appears to me to be adverse to the drudge work of detailed science. It is time they stopped talking about saving the earth and started doing the real work necessary to prove the hypotheses and giving us more information on what may need to be done.

Why is this important? Because deniers like me say there is none. Luke-Warmers and warmers believe in varying amounts of slowing of the surface cooling, and some alarmists say the backradiation actually raises the temperature of the material above the level that the short wave can make it. Even if everyone suddenly went sane and decided there was only a reduction in the rate of cooling (faster warming also) it would be good to actually quantify by empirical experiment exactly what the magnitude of the effect is.

This one paragraph shows how hopelessly confused you are about something that is just basic physics! You make this distinction between “rais[ing] the temperature of the material above the level that the short wave can make it” and “a reduction in the rate of cooling”. There is no such contradiction between those two pictures: CO2 slows the rate of cooling and, in doing so, it causes the temperature of the earth to be warmer than it would be in its absence because the earth is heated by the sun and its steady-state temperature is determined by the balance between the rate at which it receives energy from the sun and the rate at which “cools itself” by sending energy back into space.

The fact that you have been unable to comprehend this shows how you are unwilling to allow yourself to comprehend the most basic of scientific principles.

Yet, that statement says NOTHING about the magnitude of the effect on the earth itself.

The magnitude of the radiative effect of CO2 is not under debate in any serious quarters. Roy Spencer and Richard Lindzen and the rest of the scientific community all agree it is 3.8 W/m^2 (+/- 5%, or at most 10%). The magnitude of the resulting temperature change is still under debate, but this involves the question of feedbacks, which alas can’t be settled by any experiment smaller than the entire scale of the earth. (Which is not to say we can’t learn a lot about feedbacks from empirical data. In fact, we can and have. See, for example, here: http://www.sciencemag.org/content/310/5749/841 )

“CO2 slows the rate of cooling and, in doing so, it causes the temperature of the earth to be warmer than it would be in its absence because the earth is heated by the sun and its steady-state temperature is determined by the balance between the rate at which it receives energy from the sun and the rate at which “cools itself” by sending energy back into space. ”

You have very bad radiation, the Earth cooling and the energy content concept here. 0.04% CO2 in the atmosphere has absolutely minimal energy content in it when comparing the energy content of the atmosphere (orders of magnitude more than CO2) not to mention the LW radiation energy from the Earth surface (orders of magnitude larger than atmosphere). I guess you know the mathematical differention of infinitely small -> 0, thats CO2 capable of warming the air -> 0, warming the Earth -> 0 and CO2 capable of slow cooling -> 0. CO2 cooling warms the Earth is absolutely absurd if you have any energy concept at all. Warming and cooling are mainly due to huge amount of water presents on the Earth. The movement of water causes most weather changes. I would advise you to appreciate the energy contents in them and study the physical properties of water, CO2 and the energy they are involved or you will never learn and keep on misinforming the general public wasting your life unless you have an agenda in order to stay on the gravy train.

The Earth receives the Sun energy, stores (chemically and physically) some of it, reflects some of it, refracts some of it, conducts some of it, convects some of it, radiates (naturally including decays, volcano eruptions, human consumptions of food and fossil fuels) some of it. The Sun itself also in an ever changing state of emitting energy. There is no steady state temeperature, only instantaneous temperature.

The fact that you have been unable to comprehend this shows how you are unwilling to allow yourself to comprehend the most basic of scientific principles of energy, cooling, heating and radiation.

Sam NC: It would have been more precise of me to talk about the rate at which energy is emitted or absorbed by the earth. Yes, the conversion of this into a rate at which temperature changes involves the heat capacity which, as you note, is largely due to thelarge amount of water. However, this doesn’t change the end result, i.e., the final steady-state temperature, but just how long it takes to get there. [Of course, this ignores water vapor or cloud feedbacks, which can affect the end result.]

The fact that you have been unable to comprehend this shows how you are unwilling to allow yourself to comprehend the most basic of scientific principles of energy, cooling, heating and radiation.

Well, if I fail to comprehend this, I am in good company with basically all of the scientific community. Why do you think you understand these things better than the National Academy of Sciences, the authors of the major physics textbooks which discuss global warming, etc., etc.? You are just fooling yourself…It is the Dunning Kruger effect ( http://en.wikipedia.org/wiki/Dunning_kruger_effect ).

Look, if you want to believe nonsense, I can’t stop you. Go play with your fellow travellers who believe the Earth is only 6000 years old and all the rest of the folks who would rather believe pseudoscience than science that conflicts with their ideology. Ignorance can only be cured if someone wants to learn. You want to remain ignorant and so you will.

To Judy: It is clear that you miss the points I want to make. Of course there are endless little things you can focus on and question, but in the spirit of Leibniz I ask you to try get the main message. I am not saying that my model is perfect. I try to make a point about radiative heat transfer based on a mathematical analysis of the same equation Planck tried to use but gave up with. If you focus on this equation, do see something of interest in my analysis? What is your model for radiation? Does it contain “backradiation”?
Is it a stable phenomenon in your model?

Next, you said you did not like Kiehl-Trenberth, and I asked you why? I do it again.

And have you given your students my chapters for homework? It could be an educational experience, and students need assignments, right?

To Maxwell: A warm body also absorbs low frequency waves but re-emit them
and thus avoid getting heated by low-frequency stuff. Like an educated person
simply does not get heated up by silly remarks from uneducated, only by remarks from more educated. Right?

Claes, to me, that seemed to be a weak response to a very clear post by Maxwell. You wanted Judith to give you the opportunity to debate the science contained in your book, so debate it properly rather than handwaving away difficult objections.

Without warming the warm body with low frequency light from the colder body, there is lack of energy conservation. In order to emit more low frequency light (ie the low frequencies already being emitted and the absorbed low frequencies from the colder body) the thermal equilibrium must change, coming to a higher temperature according to the Stefan-Boltzmann law. Raising the temperature costs energy.

So there are two options 1) your theory violates the conservation of energy because the emission of low frequency light by warmer blackbody doesn’t change in response to increase flux of low frequency light from a colder blackbody or 2) conservation of energy is preserved and your thesis (cold blackbody can’t heat warm blackbody) is wrong.

I’ll let you pick which options you want.

With respect to your poorly thought out classroom analogy, I am constantly learning from people who have less education than me. On an almost daily basis in fact. So not only is your analogy not informative in the context of energy transfer via radiation, it’s as fundamentally incorrect as your physical theory.

One thing that may be overlooked, in these discussions on whether or not a cold object can heat a warm body though exchange of radiation is that, a photon doesn’t know where it came from, the only thing it “knows” is its frequency. All the properties, momentum, wavelength and energy are directly related to its frequenncy and vice-versa. Measure one of the four and you know all of them.

The trouble with photon particles carrying energy back and forth is that it is
an unstable phenomenon, or do really think there is a highway with left
and right lanes connecting two bodies? Why would photon respect such
traffic laws? Which equation is describing the physics you are hinting at?

Why does there have to be left and right lanes, or what happens when two photons traveling in opposite directions reach the same point in space?

Do they collide, or interact in anyway?

Or do you have anything other than handwaving to support this statement from your book?

“We argue that such two-way propagation is unstable because it requires
cancellation, and cancellation in massive two-way flow of heat energy is
unstable to small perturbations and thus is unphysical.”

Why would it be unstable? In second chapter you obtain an equation witch is the same as Boltzmann law for 2 bodies and infinitely small T difference. So conclusion about stability should be the same. By the way, your equation is not symmetrical, meaning that cold and hot temperature have not the same influence. So how do you generalise to a N>2 body problem? Looks trickier than classic Boltzmann to me.

But more important, you throw out quanta interpretation. Sure it is not intuitive, but since Boltzmann it has been used to derive a huge amount of physical equations, and explain a lot of experimental results. Throwing out quanta to obtain radiative transfer equations you like better is only the begining of the story, because now you will have to reinterpret THE major part (more important imho than relativity) of modern physics ( post WWI physics). This is not out of question, but it is a huge task, and a task far far far too big to start from just radiative heat transfer…even if historically it was the start up of quantum mechanics. To make such a body of inference collapse, a single new fact may be sufficient, but the new fact will usually not be the same as the one at the origin of the old theory, and the new theory should be as powerful as the one it replace. Not bearing well for your new interpretation, so yes, even if I like the first chapter a lot, the second one is definitely in crackpot territory…

I notice you have avoided the challenge of applying your theory to a real world problem such as heat loss from a pipe, the concept of a cooler body transferring heat to a warmer has great success in these situations and has been tested many times. Cut to the chase, try some of the problems on page 582 of Mills, ‘Heat and Mass Transfer’.
Here’s a link in case you don’t have a copy.http://tinyurl.com/4e63abx

Believers in the greenhouse effect will not honestly take in information counter to their belief, no matter how it is couched. As long as everyone pretends that there is a legitimate scientific debate being engaged here, it is obvious that situation will continue unchanged. Meanwhile, the truth lies elsewhere than the mass of climate scientists, and the hapless public, supposes. What follows is a comment I started to post on Claes Johnson’s site a few days ago, but didn’t because I realized no one was listening. I’ll put it here just because I exist, and the facts exist, and it has to be said, and eventually admitted by everyone:

You need to establish first how the atmosphere is basically warmed: By atmospheric absorption of direct solar infrared irradiation, or by surface absorption of visible radiation followed by surface emission of infrared. Climate scientists, and their defenders, who tout the greenhouse effect, believe the latter [which leads to the infamous backradiation], and ignore the former.

But as I have tried to communicate, to other scientists and to the public (see my blog article, “Venus: No Greenhouse Effect”), comparison of the atmospheric temperatures of Venus and Earth at corresponding pressures, over the range of Earth atmospheric pressures (from 1 atm. down to 0.2 atm.), shows the ONLY DIFFERENCE between the two is an essentially constant 1.176 multiplicative factor (T_venus/T_earth) which is just due to the relative distances of the two planets from the Sun. Nothing more. It has nothing to do with planetary albedo, or with the concentration of carbon dioxide or other “greenhouse gases”. The only (small) deviation from this general condition is in the strictly limited altitude range of the clouds on Venus (pressures between about 0.6 and 0.3 atm. only), where the Venus temperature is LOWER (not higher, despite the carbon dioxide atmosphere) by just a few degrees than the strict 1.176 x T_earth relationship, due no doubt to the cooling effect of water (dilute sulfuric acid) in those clouds.

The only way this overwhelming and definitive experimental finding (T_venus/T_earth = essentially constant = 1.17 very closely, encompassing the data of two detailed planetary atmospheres) can be explained is that the atmospheres of both planets are heated by the SAME PORTION of the solar radiation, attenuated only by the distance from the Sun to each planet. This means absorption of visible radiation at Earth’s surface, followed by surface emission of infrared (heat) radiation into the Earth atmosphere, cannot have anything to do with the basic warming of the atmosphere, because Venus is largely opaque to the visible solar radiation, and it cannot reach Venus’s surface (and is thus not part of that common portion warming both atmospheres).

So the first unarguable fact is: Earth and Venus are both warmed by direct atmospheric absorption of the same infrared portion of the solar radiation. There is no speculation, no theory in this statement: It is an amazing (because so many scientists believe otherwise) statement of experimental fact, based on the actual detailed temperature and pressure profiles measured for the two planets (which have been available to climate scientists promoting the greenhouse effect for nearly 20 years now, which means they are incompetent). And it completely invalidates ANY “greenhouse effect” of additional warming by adding carbon dioxide to the atmosphere: Venus has 96.5% carbon dioxide (compared to Earth’s 0.04%), yet its atmospheric temperatures relative to Earth’s atmosphere have nothing to do with that huge concentration, but only and precisely to the fact that Venus is closer to the Sun than is the Earth. Venus’s surface temperature is far higher than Earth’s, because Venus’s atmosphere is far deeper than Earth’s. To tell the public — and to teach students — otherwise is to recklessly spread an obvious falsehood and steal hard-earned knowledge from the world, thereby misusing and ultimately defaming the authority of science in the world.

Stop playing around with theoretical put-downs, and talking past each other, and admit that the Venus/Earth data completely and unambiguously invalidates the greenhouse effect.

Claes starting point is not concerned with the climate change issue as such.
His contribution is to question if Plank and Einstein were correct to abandon classical wave theory in favour of the quantisation of electromagnetic radiation.
To be sure Plank and Einstein were deeply unhappy with the situation and regarded the concept of the photon as a “fix” or even a “trick” which would give way to some fuller explanation of phenomena like the photoelectric effect and so on.
IMHO the photon explanation is the best we have at the moment but I’m glad that imaginative people like Claes are ready to reexamine the fundamentals from time to time.
I’m sure if a real problem about heat transfer required a solution Claes would produce a solution that competent Physicists would agree with.
He would probably use the Poynting vector to give the direction and magnitude of heat flow.
Which of course as Clausius pointed out is always from higher to lower temperature bodies.
On the climate change issue he would say I’m sure that the colder atmosphere cannot increase the temperature of the warmer Earth Surface.

”
His contribution is to question if Plank and Einstein were correct to abandon classical wave theory in favour of the quantisation of electromagnetic radiation.
”

And he, in turn, throws out the superposition principle ( the two black bodies’ radiation patterns can be solved for indepandantly, and then added together), which holds for classical wave theory. I don’t see switching to a classical EM frame, and then having to destroy a central tenet of the classical EM theory an advance. You can’t have it both ways – classical EM holds and classical EM doesn’t hold. The very frame it’s put itno says his theory is flat 100% wrong.

Maxwell posts:
“But the train gets off the tracks pretty quickly after that. The author makes the statement,
‘The net result is that warmer blackbody can heat a colder blackbody, but not the other way around.’
which is obviously wrong.
But why?”

One warm body in dark space radiates energy in all directions except back at itself (ignoring internal self-balancing). Two warm bodies in dark space do that but also each warms the other which reduces the rate at which they cool. This is true regardless of relative temperatures. The cooler body radiates the warmer body (can’t be helped – it doesn’t know it is the cooler body and science doesn’t care) and that unavoidably slows the rate of cooling of that warmer body.

Unlike electricity passing through a straight taut wire (and a tapered wire will demonstrate distributed radiated energy), no part of the wire radiates any other part of the wire. It is like that solitary radiating body in space. The thermal distribution is a consequence of the local resistance and thermal conductance.

Not the case with radiated energy. Each object paints any other visible object and that object is compelled to react to that energy.

OK, I’m late to this and have what may be a very dumb question. But, dp, in the scenario you posit isn’t it possible, depending on the temperature, size, and proximity of the two bodies, that the cooler may actually increase in temperature, at least for a period of time, while it is never possible that the warmer object would increase in temperature? And isn’t that the point some are making, i.e. the colder body can not warm the hotter body?

The warmer body does indeed warm the colder body, but at the same time the warmer body gets also warmer than it would be without the colder body. It would still radiate as much as without the colder body and this radiation would disappear to the empty space. What the colder body does is that it is also radiating (although less) and some of this radiation is going to hit the warmer body and bring some heat to it. Some additional heat is heating the body whatever its source is.

If the colder body causes the warmer body to heat then the radiation of the warmer body will increase and it should be measurable. If we cannot measure it the effect is so small as to be ignored in the context of the climate debate (much larger effects are ignored by the Models). Can you point us to papers showing the experimental data on this?

No one else has bothered to beat us over the head with the actual empirical data, that I have seen, and my head is really hard so takes a lot to penetrate it.

Claes, I could recommend some books on statistical thermodynamics if you’re interested. It seems to me that if one is going to dismiss it as “jibberishy” one ought to know something about it, if one is not to be be considered a crank.

To David: I have tried to learn from books on statistical thermodynamics but
I belong to the large group of mathematicians who cannot understand what
this theory tells you about reality.

As Harry DH says: A constructive debate requires constructive minds. To argue
with a three year old who has decided to not do something, requires something
else than good old logic.

Yes; it is a good idea to go back and understand that Planck and Einstein and Schrodinger were not happy at all with particle statistics. Maybe they had
some good reasons not to be which are still valid.

Right, they are challenging Planck and Einstein so we should prove it.

From the chapter on Blackbody radiation:

“7.13 Stefan-Boltzmann’s Law for Two Blackbodies
The classical Stefan-Boltzmann’s Law R = T 4 gives the energy radiated
from a blackbody of temperature T into an exterior at absolute zero temperature
(0K). For the case of an exterior temperature Text above zero,
standard literature presents the following modification:
R = T 4 − T 4
ext, (20)
where the term T 4
ext conventionally represents ”backradiation” from the
exterior to the blackbody. It is important to understand that this is a convention
which by itself does not prove that there is a two-way flow of
energy with T 4 going out and T 4
ext coming in.
In our analysis, there is no such two-way flow of heat energy, only a
flow of net energy as expressed writing (20) in the following differentiated
form
R 4T 3(T − Text) (21)
with just one term and not the difference of two terms. The mere naming
of something does not bring it into physical existence.”

If you have two bodies, or one body radiating to an exterior, which can be considered as two bodies. They both are radiating, and how do they know of the existence of the other, which would be required to determine the magnitude of the net flow of energy.

Pretty much requiring inanimate objects having knowledge of other inamimate objects is what your analysis requires.

We can detect the cosmic background radiation, and those photons, when they enter a detector, must add that energy to the detector in order to satisfy consevation of energy, which warms the detector, slightly. That cosmic background radiation is just blackbody radiation extremly red-shifted.

I guess we are getting somewhere, as those who are trying to disprove the greenhouse gas effect, realize that in order to do that, they must attack Einstein, Planck and the Photon, and you wonder why they are labeled crack-pots.

I often find challenges to my existing perspectives to be enlightening, because in responding, I’m forced to review my own understanding, and on ocassions, revise it. In this case, however, the claim that a cooler body can’t cause a warmer body to become warmer still (if that is indeed claimed) is so nonsensical that it would be hard to learn anything from refuting it. Instead, I will simply suggest a simple experiment.

I assume most of us are located in what is now a relatively cold time of year. Here is what I suggest. When the temperature outside is 2 deg C and your body skin temperature is, say 35 C (measured by a thermometer taped to your skin and insulated to shield it from the outside), go outside dressed only in a short-sleeve shirt and shorts, wait for about an hour, and then take your temperature. It will be lower – record the value. It might be around 32-33 C.

Now go back in the house, and put on heavy clothes and an overcoat, taken from the closet at 20 C (obviously colder than your body skin temperature). Again, take your temperature after an hour.

Did the 20 C clothes cause your 32 C temperature to go up or down?

The mechanism of warming by the clothes is primarily convective, while the warming of the surface from the atmosphere is primarily radiative, but the principle is the same – a cooler body can cause the temperature of a warmer body to rise. For this to happen, of course, the cooler body must itself be exposed to heat that originated in an even warmer source than the current temperature of the warmer body. In the absence of such a source, a cool object can’t raise the temperature of a warmer object (although it can cause it to cool less than if the warm object were simply radiating to space). For your skin, that heat is generated by metabolism sufficient to maintain your internal temperature above the 32 C skin temperature, and the clothes retard its escape. For the atmosphere, the heat comes from the sun, and is transmitted to the atmosphere by absorption of solar radiation and IR radiation from the surface. Ultimately, of course, the net heat flow is from warm to cold – from the sun, via various routes, to the Earth, and then to space. In the meantime, the greenhouse effect operating on the atmosphere makes the Earth’s temperature habitable.

Fred, with all due respect, everyone here understands conduction and its little brother convection (and convection’s little brother advection) just fine. The nonsensical greenhouse gas theory is based on radiation and radiation balance causing heating. Bringing conduction, convection and insulation into the conversation is off-topic and a distraction…and certainly seems intentional to me…like a magician trying to distract the audience from the things going on in his left hand.

……”In this case, however, the claim that a cooler body can’t cause a warmer body to become warmer still (if that is indeed claimed) is so nonsensical that it would be hard to learn anything from refuting it. Instead, I will simply suggest a simple experiment.”……..

During a school lesson the Physics teacher might say the force of gravity causes “bodies” to accelerate towards the Earth at 9.81m/s2.
A pupil might ask “is the body alive”.

Fred we are not talking here about heat sources that have a means of regulating their power output such as an animal.

Will putting clothes on a bronze statue at a temperature of say 350K cause its temperature to rise above 350K if the ambient temperature is say 275K?
Of course not!
All the clothes can do is to insulate the body i.e. to reduce the rate of heat loss from the object.

Fred, I do hope you are joking here as the reason I will be warmer after putting on the 20c clothes is the energy I’m burning and turning into heat (you know, calories) will not be lost as quickly allowing my body to warm.

Ken – Your explanation is correct, but there was no joke intended. The point is simple – as long as a heat source is available for the cooler object to operate on, that object can raise the temperature of a warmer object. In this example, the heat source is body metabolism. For the greenhouse effect, the heat source is the sun. The inability of a cooler object to raise the temperature of a warmer object applies when there is no source of heat for the cooler object to divert back toward the warmer object, but that is not the case with our atmosphere.

if a reader came to the conclusion that Fred was discussing convection or conduction it would point more to reader’s inability to decipher the most important aspect of the his example rather than a real lacking on the part of Fred. Yet, here you are.

Actually I don’t understand Fred.
Let me see, if I put a brick out in the sun and it warms to X degrees, and if I then split the brick in 2 and seperate them a couple of centimetres, they will “become warmer still”?

Possibly yes, because of increased surface exposure to sunlight, but it depends on air temperature, the absorptivity of the bricks for solar and IR wavelengths, their IR emissivity, conductivity and temperature at the surface they are resting on, and other variables.

I don’t know why you would introduce all those variables. It’s the one brick under the one sun sitting on the one surface. All I do is tap it with my trovel and split it in half (like a good brickie would) the properties of the 2 halves are identical. If it’s T rises due to the greater surface area, what has that got to do with the discussion about a cool body increasing the T of a warm body via radiation?

OK we’ll void the extra surface area by placing a brick under the sun until it reaches X degrees. We now get a 2nd brick from the shed and place it next to the first one.
Will the T of the first one now rise above X degrees because a 2nd brick was placed next to it?

Why are you mentioning the mean T? The moon has a T of 107DegC during the day. If we introduce a cool body next to it (an atmosphere) will it increase the moons T? It’s a simple question expanding on our discussion so far. You didn’t introduce ‘mean’ or day night into the brick example.

At equilibrium, the temperatures won’t change as long as the new surfaces have the same physical properties (emissivity/absorptivity) as the original surface. That is because the moon’s temperature is determine by the level at which radiative loss to space equals radiative gain from sunlight. Since splitting the moon won’t change the incoming solar energy in W/m^2, the outgoing flux and therefore the surface temperature won’t change.

Rob – the extra surface area would both absorb and radiate more heat. The temperatures would remain unchanged, because they are dictated by solar absorption on a W/m^2 basis. Surface area is therefore irrelevant.

I don’t understand your (Moolten’s) point either. Clothing does not heat up a human body via “back-radiation” or “back-conduction.” There is no heat transfer from cold to hot without work input (Clausius), and clothing (and likewise the atmosphere) cannot add work input.

“The total surface area of an adult is about 2 m^2, and the mid- and far-infrared emissivity of skin and most clothing is near unity, as it is for most nonmetallic surfaces. Skin temperature is about 33 deg C, but clothing reduces the surface temperature to about 28 deg C when the ambient temperature is 20 deg C. Hence, the net radiative heat loss is about Pnet = 100 W.”

Clothing “reduces the skin surface temperature” because the human body has to supply heat energy to the colder clothing to increase the temperature of the clothing. Clothing does limit convection, as do glass panes in a greenhouse, but CO2 has no such ability. Thus, the analogy fails.

Please point me to a textbook of physics which contains the terms “back-radiation” or “back-conduction.”

“I belong to the large group of mathematicians who cannot understand what
this theory tells you about reality.”

It is impossible to take anything you say seriously when you make statements like this. When classical thermodynamics fails to explain the specific heat of your atomic crystalline solid, to where do you turn? Maybe you can guess what technique Einstein used to model the solid.

Interesting. You choose a classical frame for your work, and then use a statement about the interpretation of QM wave functions to boslter your argument .. but fail to note that Einstein didn’t distance himself from statistical mechanics, etc.

I see no clarity in your thoughts or arguments, merely throwing in red herrings instead to answering the obvious inconsistencies which result from your theory .

Judy says that something is wrong with the KT energy budget, but refuses to
tell what is wrong. What kind of debate is this? Is it some kind guess play?
So Judy, please tell me now what it is you find is wrong with KT?

Exactly when and where have I said something is wrong with the KT energy budget? KT’s numbers are almost certainly inexact. Attempting to do some sort of globally averaged energy balance may not be the best way to go about it. But that does not mean that atmospheric infrared back radiation does not exist.

To Fred Molten: Can you give me the equations you are using showing that
heat by itself (without external input of energy) can move from cold to warm?
Of course putting on clothes makes it possible to keep a higher body surface temperature but the heat comes from the catabolism of your body, not from your clothes, at least if you live in Sweden.

The present physical theories are perfectly able to describe all basic processes that need to be considered in analyzing atmosphere and they have been tested extensively in very many different setups. There are no reasons to replace any of this knowledge by some conflicting physical laws. Most physicists are, however, unaware about, how much of the physical understanding can be described in several different ways. Handling of electromagnetic radiation is one good example.

One of my former colleagues did theoretical research on laser physics. Most descriptions of lasers start immediately with quantum field theory, but his approach was based on classical electromagnetic field theory and it was very successful. It was not in contradiction with quantum mechanics, but the mathematical approach was very different.

I can see in Claes Johnson’s texts superficial similarities with that approach. The way quantization is brought into the calculations can be chosen from several alternatives. In some approaches it can make sense to state that there are not forward radiation and back radiation, but only the net radiation. If the final results differ from the conventional approach they are certainly wrong as the conventional approach has been validated so well, but the alternative approach may also be correct as long as it leads to the same results.

I do not believe that the alternatives would often be easier to understand or of any particular value, but I would be careful before declaring some non-conventional approach automatically wrong. The case of analyzing lasers that I mentioned at the beginning is proof of the fact that sometimes one may indeed find advantage from postponing the quantization and using classical formulation as far as possible.

Using obscure alternative formulation and vague argumentation as evidence on weaknesses in the conventional understanding of physics is another matter. When it is done in parts of physics, which have been applied widely for years without any conflict with observation, I would not give any weight on such claims.

Johnson versus maxwell.
no other commenters allowed. People can then see that Johnson will not be able to maintain his position. we will them ask him to admit his honest error and ask the publishers to correct the book.

As publisher of the North American and Oceania version…I accept this challenge. I’m happy to publish errata and a new edition if and when the errors reach a critical mass.
I’m not sure how to prove anything when the topic gets this esoteric…I prefer lab experiments where the data verifies or falsifies a claim. No models. No dueling weblinks or appeals to authority in any form. It makes things tough when you need a vacuum to isolate the experiment from conduction and convection effects. We’ll see how it goes, I suppose.
Good idea, Steve.

Thank Ken. I suggested the same thing for the IPCC. We need to make room for the admission and correction of honest error. The IPCC could not do it. I do not trust them as a consequence and thus am forced to look at primary research on my own to come to a considered judgement.

Now that we have aired some stuff, I agree that the discussion is best left to those with a degree in physics (maxwell, pekka, and there are others among the denizens of climate etc that have not shown up).

I’d be down for this ‘cage match’ if I thought it would do any good. Alas, we’ve seen that even when faced with the idea that his theory violates the conservation of energy (the 1st law of thermodynamics, the very theory he claims supports him), he is unwilling to concede or even engage.

It’s my opinion, based on this fact and the lack of transparent discussion perpetuated by some other commenters, that science is not of interest to these people. Maybe it is an ‘honest’ mistake that Johnson has gotten to this place, but I see his poorly thought out analogies beginning Chap. 2 as a way for him to rationalizing away the physical meaning of some of the most well-known and thoroughly tested laws physics has given us thus far. In such a case I have to wonder how much honesty is involved…

a good historical example of what you are saying is the Drude model. It posits that electrons are classical in enough numbers when confined in a solid. There is a basic kinematic equation describing the force acting on each electron that, when solved for the appropriate situation, gives an answer that fits ‘reasonably well’ to observations. You may be familiar with this model if your friend works on lasers.

But the Drude model, and other so-called ’empirical models’, is flawed physically. Just as your friend’s laser theory is flawed. That is to say, it is practical for a well-trained experts to use such a theory because he/she understands its flaws and faults. It works for back of the envelope calculations which are quite important in the lab.

What happens when we are trying to determine a ‘physical understanding’, however?

In such cases, it’s my opinion that we must do our damnedest to get to the meat of a problem. Even if that means dispelling a computationally practical and useful formalism like the Drude model. Because the Drude model doesn’t give us transistors or quantum wells or superconduction…or lasers for that matter. Having relied on the Drude model takes away from our understanding of reality.

In the same way, while Mr. Johnson’s attempts might seem like an interesting facet of science, they fundamentally take away from a broader understanding of reality. There is no basis in it’s being real other than the words on a pdf. It is especially problematic since so many here are willing to simply regurgitate his memes without any skepticism at all.

I think the most important aspect of doing science, as Mr. Johnson claims he is doing, is determining whether or not you can handle being wrong. If you cannot handle such an outcome, as Mr. Johnson’s reaction to the criticism he has faced here makes me think, you are not interested in science. I don’t think Mr. Johnson is interested in science.

You and John Sullivan utterly mis understand the concern about the “united front”
If, for example, the AGU were to offer some session time to discuss skeptical
issues, the first question is WHICH skeptical positions should be given time?
If, for example , a research center were to open its laboratory time to test skeptical ideas on GCMs WHICH skeptical positions should be given time.
It was a PRAGMATIC discussion about a PRACTICAL problem.

Now then warmists could pick the WORST skeptical ideas and only discuss those. this is what realclimate does.

As far as I remember RC has covered just about every paper which has been promoted by the skeptics in recent years.
In the end there aren’t good skeptical ideas and bad skeptical ideas, there are just good and bad ideas, and good ideas will generally get proper consideration.
Maybe there are some exceptions – if someone can provide evidence that there are good, credible ideas out there which are not being considered then fine, until then I remain, well, skeptical.

I will be glad to give you an example of bad ideas that RC still supports. Hockey Sticks. Have they admitted yet that Mann’s and associated work are all severely flawed and should be withdrawn? That they do NOT support the claims they make?

Ref. your comment yesterday at 11:48 pm, for Andrew to “ .. Dig harder man!!! .. ”, he had the opportunity on 1st July and because he refused to remove his blinkers he threw it away. Investigative science journalist? – pull the other one.

Montford is a “respected investigative science journalist” by what standards exactly? Has he won awards of his colleagues? Has his work appeared in prestigious publications?

I haven’t read Montford’s book but my experience is that those who have make lots of charges regarding Mann that they can’t actually defend, most likely because they are false. (At least if they are true, noone has provided evidence to rebut my evidence that they are false.) I am not sure whether they got this info from Montford but that has been my impression.

Joel, instead of waffling from a position of ignorance try reading the book and following the references, do your own assessment then go over to the blogs of Steve McIntyre’s blog (http://climateaudit.org/) and Andrew Montford (http://www.bishop-hill.net/) and try to convince them that you know better than they do. Let me know how you get on. They may let you co-author a paper with them on the subject.

Well, next time I find it in a bookstore, I will look through it and see what it has to say about the “censored” directory and about the Tiljander proxies. If it just repeats the same unsubstantiated nonsense that I see from people like “Smokey” on WUWT, I will be very unimpressed. If not, then maybe it is more worthwhile.

Joel, rather than reading the books, try going to their websites and reading the archives. Especially Climate Audit, Steve McIntyre’s site, as he was central to debunking the Hokeystick. You might even ask him directly about the “censored” directory with r2 information that was not published as he wrote about it first I believe.

Of course, even if that was an inflated anecdote by some unknown person, the fact is that the r2 statistics for the Hokeystick FAILS! The difference is whether Mann knowingly misled people or is just sloppy and ignorant about the statistical methods he uses.

To Pekka: You seem to agree that macroscopic physics cannot be modeled by
quantum mechanics, and so macroscopic equations are needed for atmospheric radiation. Now macroscopic radiation seems to be well described by Maxwell’s equations, modulo the difficulty of the ultraviolet catastrophy, which destroys everything. What I suggest is a rational way to avoid the catastrophy and keep the great advantage of Maxwell’s equations as compared to primitive particle statistics. Isn’t that something to think of a bit, in the spirit of Planck and Einstein, rather than dismissing without reflection?

And the radiative transfer equations are much cruder than Maxwell, right?

Claes,
I do not agree that quantum mechanics cannot be used in those parts of atmospheric physics, where it has been used. What I was saying that in some situations the agreement with quantum theory can be obtained in surprisingly many different ways. Even for effects where the quantum theory differs from traditional classical physics the correct results may sometimes be obtained in ways where the quantum effects are somehow hidden.

Hamiltonian formulation of mechanics allows for presenting some quantum effects in less common fashion etc.

Einstein was not happy with quantum theory. I think that the main reason is related to conceptual difficulties in joining it with general relativity described in the elegant ways that he had developed. His dissatisfaction came out also in his statement about God not playing dice or in his paper with Podolski and Rosen, which has now been proven to be in conflict with experiments after Bell had formulated his inequality along the lines of that paper. In this case Einstein erred and quantum mechanics prevails.

The problems in interpreting quantum mechanics are also related to some of the possibilities of doing the calculations differently. The quantum mechanics is, however, extremely successful in giving correct predictions with high accuracy. Thus it is a very good and valid physical theory in pragmatic sense. Most physicists do not worry about the philosophical problems and do their work successfully. Whether the philosophical difficulties turn out to have some relationship to the next paradigm, which would solve the problems of Einstein and unify gravity and quantum mechanics in a elegant way, remains to be seen. Perhaps not by our generation, but our children or grandchildren.

I am still not telling the name of my former colleague, but I can tell that he has been later professor at KTH. When we were working at the same institute, we had some very interesting discussions on the foundations of quantum mechanics.

I add that sometimes it has also turned out that results generally thought to depend on quantum mechanics turn out to be true in more general settings. This is not very common and I cannot give examples, but I have certainly heard about such cases.

Claes,
Concerning back radiation I certainly believe that it is a useful concept and that the radiative energy transfer can be handled most easily by including it in the calculation. I cannot figure out, how all correct results could be obtained without considering it explicitly. On macroscopic level avoiding it may be possible, but on the more detailed microscopic level it seems almost impossible, but only almost.

Mr.Johnson:
In your description of a IR camera you admit that the instrument , directed appropiately, show radiation. At the same time you negate that this radiation reflect some reality. Could you please explain this ? I am extremely confused.

Dr. Spencer says in his article: “So, once again, we see that the presence of a colder object can cause a warmer object to become warmer still.”

However, the process he refers to is not heat transfer by radiation from a colder system to another system, but a kind of isolation, like in a thermos. Yet, the colder system is not providing “more” energy to the warmer system, but just would be avoiding that the warmer system emits heat towards the colder system. This argument is not true because the thermal energy is transferred to the colder system, invariably, unless the colder system is a perfect reflecting material or the colder system has a very low heat capacity. I would make Dr. Spencer to recall that the Earth is not a thermos; his argument could be possible if the highest layer of the Earth’s system, i.e. the thermosphere, had a mass density higher than that of the surface. It’s not the case for the real Earth.

On the other hand, if you wish to consider QM on this thread, you must include also the well-described by Einstein induced emission, which has been corroborated experimentally and in the construction of some devices, and the well-know and demonstrated radiation pressure. These two real physic phenomena debunk any idea of a “backradiation” from the atmosphere warming the surface.

I think you are confused. Roy’s posts on this topic are very clear and definitely show that there is in fact backradiation toward the surface from the atmosphere. He ultimate experiment used an IR thermometer to measure the actual temperature of the air several hundred feet above via the IR light it emits.

Even more confusing are your statements concerning stimulated emission and radiation pressure. Can you please explain specifically how those physical processes play a role in radiative transfer or the lack there of in the atmosphere?

@ maxwell… No more than you are.
Roy’s “experiment” only demonstrates that there is energy flow by radiation, whatever his conclusions could be.
Both processses, induced emision (or induced radiation) and radiation pressure, influence radiation. If you know what those terms mean, you won’t be so confused, as you are, on “backradiation” issues.

you’re damn right I’m confused. You still haven’t provided a physical mechanism for how those interesting terms have to with the most important aspects of radiative transfer.

On the point of Roy’s experiment, what type of energy transfer is he measuring? If the IR thermometer is conducting energy from the surrounding air, his thermometer would have measure about 300 K. Instead, his thermometer read around 200 K. Where does that difference come from in terms of energy transfer? Are you saying that the thermometer can conduct energy from the upper reaches of the lower atmosphere without conducting through all the layers?

That would be a monumental theory!

Also, if you’re going to charge that a particular person doesn’t understand some terms you use, you should make sure you know what you’re talking about. I have extensive experience in classical optics, quantum optics, atomic and molecular spectroscopy and nonlinear optics (I built an optical parametric amplifier over the past week in fact) so I KNOW those terms you’re using have absolutely nothing to do with this discussion, the greenhouse effect or ‘backradiation’. It’s a purely quantum mechanical, spontaneous effect.

Dear Maxwell,
Please, visit again Roy’s experiment and see what the box floor is and on what kind of surface it was placed on. You’ll get the answer.
Regarding induced emission, you should not forget the natural photon streams, so upwards, during nighttime, as downwards, during daytime. On the other issue, if you make the proper calculations on radiation pressure, you’ll find that the downwelling radiation heating up the surface is not possible in the real world.
If Dr. Curry, the owner of this blog, grants me permission to go out of topic, I will proceed to answer properly your questions.
Regards,
Nasif

The experiment to which I was referring had Roy traveling around in his convertible sedan pointing an IR thermometer into the air. Not his make-shift holhraum.

In that case, where he is clearly measuring the temperature of the atmosphere directly several hundred feet above him, how does energy interact with the thermometer to produce a reading of 200 K?

I’ll give you a hint, it has nothing to do with radiation pressure.

It’s becoming more and more clear to me that you are using words that have one meaning to you, but a totally different meaning to actual optical scientists. You ought to look into the ways in which these terms are used in scientific circles so that you can more easily communicate your points in a scientific debate.

Dear Maxwell,
Don’t go further on this or you’ll get disappointed on your own limitations about those concepts. Take your book on Radiative Heat Transfer and you’ll see I’m absolutely correct. I don’t want to go further on discussing those concepts because they are out of topic and I respect the admonitions of Dr. Curry on the purpose of this blog thread.
Well, what the ground on which Roy placed his box and what the floor of the box was? Could you be so kind as to tell us what was it, specifically?
Third, when he was “meassuring the temperature travelling around on his convertible sedan”… maxwell, tell me honestly, don’t you know how thermometers work and what thing makes them work?
Regards,
Nasif

I’m trying to determine if your lack of comprehension of my comments is due to the possibility you are not a native English speaker or just plain stupidity. I’m willing to give you the benefit of the doubt and assume the first option, but not for too much longer.

Again I’m discussing Roy’s use of a IR thermometer, not his makeshift holhraum. Please make an important mental note of that fact and stop your persistent confusion over this fact. It’s making you look dumb.

An IR thermometer measures IR light (heat) emanating from a body or gas. Therefore, if Roy is pointing this thermometer at the sky, the thermometer reads the temperature of the sky via its IR emission. Therefore, the atmosphere is emitting IR radiation toward the ground that began its journey in ‘life’ at the surface, making it ‘backradation’. QED.

As for radiative transfer, I’ve extensively studied ‘Introduction to Three Dimensional Modeling’ by Washington and Parkinson. From this text I am able to recover what both quantum mechanics and thermodynamics imply should be a downwelling IR emission from the atmosphere.

Do you have other certified texts that you feel are better than Washington and Parkinson?

Furthermore, you continue to lack any sort of meaningful physical description of what you are talking about. Based on the plethora of these facts so far, I must say I don’t think very highly of your opinion on this matter.

darn, you probably will never see this to answer my question, but, just on the offchance that someone does and can:

I am under the impression that the atmosphere absorbs virtually all of the IR radiation (except the window) within about 15ft of the surface. if this is so, exactly what was Dr. Spencer measuring from the ground?? Wouldn’t downward IR also be absorbes so that all he would be able to measure would be about 20 feet over his head and not an average of several hundred feet????

The equation that models backradiation is the Planck law for the intensity of light emitted by a blackbody at a specific temperature. This equation is carried out for every layer in the atmosphere, which has a stratified temperature profile. The absorption of light, all frequencies, is modeled by the Beer-Lambert law which is easily derivable from Maxwell’s equations via the electromagnetic wave equation.

If we wanted to get down and dirty with the most fundamental equation governing the behavior of absorbing material to first order in the perturbation due to the interaction with light, we would have to use the quantum master equation with a phenomenological coupling to the vacuum field. We can go to second order in the perturbation to get to scattering processes if we liked as well.

Ever wonder why the sky is blue?

This process would allow us to see absorption and spontaneous emission (the dominant form of emission in the atmosphere) on a per atom/molecule level. The Beer-Lambert and Planck laws get the overall average effect of the quantum master equation in this context.

So from first principles, we can easily calculate (grad school quantum problems) the rate of absorption and emission of a particular molecules when the light in question is on resonance with a particular allowed quantum transition, the linewidth of that transition based on different broadening processes and the necessary equipment to test the predictions of any such calculation. From there, we can sum over all the molecules in our volume and get an answer to compare to the observational laws used in climate models.

You can see whether the agreement between these methods is good. Let me know how it goes.

For example, CO2 emits at 15 microns at an intensity according to the number of molecules and their temperature using the Planck function for temperature that wavelength (which actually peaks not far from 15 microns for normal atmospheric temperatures). This emission is seen at the ground as part of the back-radiation, together with all the other CO2 and H2O bands in clear sky that make up all the back-radiation.

The molecular properties determine which wavelengths have strong emission and absorption, i.e. they determine the emissivity, which is equal to absorptivity. Planck’s law tells how strong the emission is at those wavelength as the strength is a product of the emissivity and Planck’s law for black body at that wavelength.

When the emissivity of a gas is strong for a particular wavelength, it means that its is significant already for a thin layer and very close to one for a thick layer in accordance with the Beer-Lambert law. Then the the strength of emission at that wavelength is the same as for a black body of the temperature of the gas. This is true for those wavelengths, but at other wavelengths the gas does not emit at all or very little.

As Pekka pointed out above it sets the upper limit at any wavelength, if there is no allowed transition at a particular wavelength then the emission will be zero no matter what the Planck value is. The Co2 band at 15μm will emit strongly up to the Planck limit. O2 can emit in the UV at around 220nm but in the atmosphere the Planck limit will be generally so low that this emission will be very weak (Judith made this point earlier).

To Lucia: If you had read the equations I refer to as Navier-Stokes you would have seen that they express conservation of mass, momentum and total energy
and are the basic equations of thermodynamics describing transformation
between kinetic and heat energy through work. Are you familiar with thermodynamics?

The basic equations of thermodynamics are called “The first law of Thermodynamics” and “The 2nd law of Thermodynamics”. One of the clues is that these equations contain the word “thermodynamics”. In contrast, conservation of momentum is “mechanics” and the navier-stokes equations are basic equations for fluid mechanics.

Conservation of mass is used in analyses, but that doesn’t transform the equation into “a basic equation of thermodynamics”.

Are you familiar with thermodynamics?
I’m laughing myself to tears here. I am familiar enough to know that you are making errors. :)

To Lucia: The convective adjustment that you think is science, is just an ad hoc fix up without any mathematical basis. If you are allowed to adjust what your
equations tell you, then you can get anything you want.

Still waiting for you to apply your model to a real world example such as those which I showed above. Most applications of standard radiation heat transfer have a substantial overlap between the incoming spectrum and the emitting spectrum by the way.

Claes–
Since your paper suggests you think the first law of thermodynamics is the 2nd law, and the navier stokes equations is the basic equation of thermodynamics, I am not surprise that you think the convective adjustment is just an adhoc fix up. To understand the physical motivation, will need to apply thermodynamics. At my blog I gave you a tip on how to distinguish the first law from the second:

The second law should contain an inequality symbol ≤, a symbol that represents entropy (S is often used), and a symbol to represent temperature (T is a popular choice, but rebels sometimes use θ). Also, if I recall correctly, it generally contains no work term (i.e. W would not appear.)

As for this:

If you are allowed to adjust what your equations tell you, then you can get anything you want.

Lucia,
I did not check carefully, but I think the equations that Claes is presenting do present correctly the second law. The inequality is hidden in the requirement that D ≥ 0.

The formulation is not the one we all have seen most often, but I think it is correct.

The same statement that Claes presents correct formulas in a less conventional way seems to apply to the other chapter as well, but there I have doubts on, whether all equations are correct or only some of them. I did not read in this text at all carefully or study the equations more than superficially as I do not think that his approach is useful even when it is correct. Many of the claims in the text are strange if not outright wrong.

Pekka–
Specifying 0≤D where D is dissipation is a consequence of the 2nd law of thermodynamics. However, it does not turn those equations into the 2nd law.

That equation may be a correct representation of something but it is not the 2nd law of thermo. This is not a matter of notation. Other puzzling things about that equation may have something to do with non-conventional representations — for example, it’s not clear to me that it’s even a correct formulation for the first law. But in order to pinpoint the problems, I need to know whether that’s supposed to be a control volume formulation or an analysis on a fixed volume, and possibly where the boundaries are etc. My impression is it’s supposed to be a control volume with the top at the top of the troposphere– but if so quite a few terms may be missing. (Or not. It depends on whether we have a control volume whose shape is permitted to change– in which case…. well…)

Lucia,
My purpose is not to defend the book or conclusions presented by Claes Johnson in the book. I certainly disagree on very many things. I am only noting that texts that are obviously wrong, when they lead to definitely wrong conclusions may not be wrong in all of their details. Most people seem to agree that this chapter is actually correct in what it describes. Its content may be used in reaching wrong conclusions outside its range of validity, but that is another matter. It is also possible that the unconventional way the equations are presented contributes to wrong conclusions, but even so the equations may be correct.

Claes Johnson presents two inequalities in eq. (2). They are equivalent when combined with the first law /eq. (4). Of course this is not the most general presentation of the first and second law, but for the problem considered they appear to be equivalent with the general formulation. It is clear that using these laws as more basic than the general formulation may lead to errors. Perhaps such an error is really done, when considering radiative processes in the other chapter. I am not really interested enough to even check.

Also in this chapter the formulas (5) and the related discussion are obscure. If not for other reasons then at least in the total neglect of considering units properly. The equations can only be valid in units where temperature is dimensionless (i.e. 1 K = 1) and the unit of acceleration is inverse of the unit of length. Furthermore it is stated that specific heat capacity cp = 1. Whether all that is possible at all is certainly not obvious. But then again all that is more or less forgotten when the next formulas are standard knowledge.

The whole paper is confusing and may well be misused, but even so it is good avoid erroneous claims about its content.

Pekka–
I have never suggested things that are wrong in their results must be wrong in all their details. I am pointin
I am saying is that those equations are not “The second law of thermodynamics”. The reason I am saying they aren’t is that they aren’t.

In undergraduate fluid mechanics problems, students solving pipe flow and other simple problems, often use an equation referred to as “the mechanical energy equation” or sometimes “the energy equation”. It is derived from conservation of mass and momentum, sort kinda-sorta like the first law of thermo and includes a dissipation term. The 2nd law requires that dissipation term to be positive.

So, using that equation lets students impose the requirements of the 2nd law on their analysis. However, you don’t get to call that equation “the second law of thermodynamics” merely because it permits students to correctly incorporate the effects of dissipation on pressure drop in pipeflow.

Likewise, what Claes writes down is not the 2nd law of thermodynamics.

Moreover, I find your clain that

Of course this is not the most general presentation of the first and second law, but for the problem considered they appear to be equivalent with the general formulation.

To be rather dubious.

In fact, based on the text, I’m not convinced it is possible to pin down what “the problem considered” really is.

Dear Friends,
I come late to the interesting discussion, so I did not read through all. Therefore I do have a remark.
A flat hot body with two sides, unit heat capacity and with time dependent temperature Th(t), starting at Th(0)without an internal or external energy source cools from both sides with the rate dq/dt = sigma Th(t)^4 per unit area.
Now you put a cold body with Tc(t) adjacent, facing exactly one side without touching, the hot body cools from this side with the rate dq/dt = sigma*(Th(t)^4 – Tc(t)^4) per unit area and with dq/dt = sigma Th(t)^4 per unit area from the other side. Therefore the hot body in both cases is cooling all the time, since Th(t) is always greater or equal to Tc(t).
However, the hot body Th(t) stays in the second case warmer all the time than in the first case. But this is different from saying it gets warmer than initial Th(0). If Tc(0) is smaller than or equal to Th(0), then Th(t) is always smaller than Th(0).
Of course as Roy Spencer showed a hot body with an internal or an external energy source can get warmer than Th(0), if you put a cold body adjacent to it.
Best regards
Günter

Dear Günter…
Anyway, the colder system IS NOT heating up the warmer system, but cooling it, continuously, if we wish, but only up to the point of equilibrium, i.e. when both systems reach the same energy density. And even so, the internal or external source of heat would continue heating up the warmer system.
Take off the internal or external operator, for example, and you’ll see the colder system cannot heat up to the warmer system but quite the opposite.
It is the internal or external PRIMARY heat source what heats up the system, not the colder system. The latter is Dr. Spencer’s argument.

Dear Nasif,
that’s what I wrote if you reread my paragraph..
Therefore I said: “Of course as Roy Spencer showed a hot body with an internal or an external energy source can get warmer than Th(0), if you put a cold body adjacent to it.”
Of course it is the energy source that heats the body up.
I think it is important not to confuse “getting warmer” or “keeping warmer” with a energy source that heats a body up.
Regards
Günter

In his discussion of a hot plate next to a cold plate, Dr Roy Spencer says:

The 2nd Law of Thermodynamics: Can Energy “Flow Uphill”?
In the case of radiation, the answer to that question is, “yes”. While heat conduction by an object always flows from hotter to colder, in the case of thermal radiation a cooler object does not check what the temperature of its surroundings is before sending out infrared energy. It sends it out anyway, no matter whether its surroundings are cooler or hotter.

Yes, thermal conduction involves energy flow in only one direction. But radiation flow involves energy flow in both directions.

Of course, in the context of the 2nd Law of Thermodynamics, both radiation and conduction processes are the same in the sense at the NET flow of energy is always “downhill”, from warmer temperatures to cooler temperatures.

But, if ANY flow of energy “uphill” is totally repulsive to you, maybe you can just think of the flow of IR energy being in only one direction, but with it’s magnitude being related to the relative temperature difference between the two objects.

Clearly Spencer thinks that radiative heat transfer is completely different from conductive heat transfer, and can go ‘uphill’. He writes:

The only way I know of to explain this is that it isn’t just the heated plate that is emitting IR energy, but also the second plate….as well as the cold walls of the vacuum chamber.

Does that mean that while radiative heat transfers don’t ‘check’ to see which way to go, conductive heat transfers actually do ‘check’?

Does that mean that while radiative heat transfers don’t ‘check’ to see which way to go, conductive heat transfers actually do ‘check’?

The separation is not that clear. On molecular level even conduction may “go uphill”, but this is not visible and can be ignored. In conduction as in radiation energy goes in both directions at micro level. In conduction this is related to the motion of energetic atoms or molecules or to vibrations (phonons) in solids. The distances are usually very short. Therefore only the collective conduction is observable and described by an equation that describes only the net flow.

In radiation it is often possible to set measuring equipment to detect separately radiation in each direction. One photon may go over a large distance etc. The back radiation is thus observable and it may also be that the easiest way of calculating the net energy transfer represents separately the two directions. In some cases it may be easier to consider directly the net flow, but as I said above, this is not always true.

Does that mean that while radiative heat transfers don’t ‘check’ to see which way to go, conductive heat transfers actually do ‘check’?

I would express it differently. Conduction describes the *process* by which heat flows along an existing temperature gradient. Radiation is a something that a body *does* based on its temperature and emissivity. The former process directly involves both/all bodies that define the local temperature gradient; the latter by definition only depends on the characteristics of the radiating body itself.

The approach used in describing conduction can easily be extended to part of radiative heat transfer, to those wavelengths with strong absorption. Heat is transferred in accordance of essentially the same diffusion type differential equation in atmosphere by radiation near the center of the 15 um IR band.

For wavelengths with weak absorption this approach does not work well, because such radiation does not proceed with small steps in diffusive fashion but by long leaps to a point where the temperature may be significantly different or even escape through the whole atmosphere. Most backscattering occurs in the region where the diffusion-like process describes the heat transfer rather well. On this basis one could describe all this with the diffusion equation and remove most of the back scattering from being considered explicitly.

The way the calculations are done does of course not affect what really happens, but it affects often the way this is described.

Radiative heat transfer consist of two radiative energy flux, one from hot to cold and one from cold to hot.
Radiative heat or net radiative energy flows from hot to cold, radiative energy in both directions.
It is a little bit confusing, since “energy” and “heat” are sometimes used interchangeably, which is strictly speaking a bit wrong. However, scientists are doing that occasionally and the reader needs to bring it into context. Bad style, though.
The second law as stated by Clausius reads: “There is no change of state that only results in transferring heat from cold to hot.”
Note, it is not energy in general.
Heat in this context should not be interchanged with energy.

Look at the blackbody spectrum of an object at say 300K.
Superimpose the BB spectrum of the identical object at 400K
Now using the spectra predict what would happen if these two objects were brought closer together so that they radiate to each other.

We notice that;
1. The hotter object has at the short wavelength end, frequencies absent from the lower temperature object.

2. Pick any wavelength that both objects have in common.
You will notice that the hotter object is emitting more radiation than the colder once.
Now examine the hot surface;
It is emitting more radiation of every wavelength than it is receiving.

You can now hopefully appreciate that a colder object can never increase the temperature of a hotter object.

I understand your point, Bryan. Perhaps you agree with Guenter Hess’s comment just before yours, in which he wrote:

Radiative heat transfer consist of two radiative energy flux, one from hot to cold and one from cold to hot.

If that’s how it is, then if it were possible to block or divert the radiative flux going from the hotter object to the colder object, while continuing to allow the radiative flux from the colder object to the hotter object (a sort of diode), then the colder object would heat the hotter object.

For the hotter object to radiate to the colder it must “see” the colder object.
Since light rays must be able to travel backwards (rectilinear propagation) no such diode effect is possible.
We therefore are forced to agree with Clausius that even for radiative transfer Heat only travels from the hotter object to the colder object.
Yes I agree with Guenter Hess’s comments.

I would like to take this section of Chapter 1 as a point of departure for my comments. It says:

“We have formulated a basic model of the atmosphere acting as an air
conditioner/refrigerator by transporting heat energy from the Earth surface to the top of the atmosphere in a thermodynamic cyclic process with radiation/gravitation forcing, consisting of ascending/expanding/cooling air heated by low altitude/latitude radiative
forcing,
• descending/compressing/warmingair cooled by high altitude/latitude
outgoing radiation,
combined with low altitude evaporation and high altitude condensation.
The model is compatible with observation and suggests that the lapse
rate/surface temperature is mainly determined by thermodynamics and not by radiation.”

_____
Yes, of course they’d like to formulate a simple “model” that works this way, as some of their other conclusions might nicely fall in line, and in so doing, to re-write some laws of physics in the process, but unfortunately, their simple thermodynamic model is simply not the way the real atmosphere of the planet works, nor in fact the way the laws of physics work.

It takes hardly anything more than a few basic real world observations to provide proof that radiational balance is a far more potent regulator of atmospheric temperatrue then the authors of this book would like in their “simple” model. But then, isn’t that the point they are trying to refute? For observational proof, take the role of water vapor as an GH gas, using the predicted GCM forecasts that the planet will see higher night time temperatures due to the increase in water vapor keeping more LW radiation near the surface. Witness to this is the fact that 37 U.S. cities and hundreds of other cities across the globe set night time high temperature readings in 2010, a year in which saw a record in precipitation. Based on a their simple thermodynamic cyclic process, this result would not be expected as that additional night time heat at the surface would surely have been carried away via convective thermal processes and added to the TOA output. This increase in global water vapor, measured over the past few decades is exactly as predicted by every GCM when using well established and quantified GH physics with the addtional radiative forcing caused by the additional accumulation of CO2 and water vapor in the atmosphere. Warmer night time temps are exactly what one would expect when considering the real world (i.e. measured) absorbtion and retransmission of LW radiation by increasing amounts of GH gases in the troposphere.

Futhermore, one only needs to step outside on a calm cloud-less winter night and then step outside on a similar night when is has a nice overcast sky to feel the radiative GH effects of the water vapor in those clouds.

I would ask the authors this: how would their model explain the warmer night time ground temperatures as measured throughout the world if not for the LW radiative effects of additonal GH gases?

Futhermore, one only needs to step outside on a calm cloud-less winter night and then step outside on a similar night when is has a nice overcast sky to feel the radiative effects of a smaller delta-T between the earth’s surface and the water vapor in those clouds.

Futhermore, one only needs to step outside on a calm cloud-less winter night and then step outside on a similar night when is has a nice overcast sky to feel the radiative GH effects of the water vapor in those clouds.

A word of caution – a clear night can feel much colder than an overcast one, even if the air temperature, as measured by thermometer, is the same.
That’s because your perspiration evaporates more readily in drier air, so the perception of temperature can be largely subjective.

1. our knowledge of the extent and amplitude of the MWP is VERY uncertain.
2. The presence of large amplitude warmings is evidence FOR long term natural oscilations, it is NOT evidence against the physics of radiation.
3. The final temp is the result of many forcings, not merely C02.

Basically, your comment is OT to the discussion of the physics of the tyndall gas effect

Thank you Steven, I couldn’t have said it better myself, though I would welcome a discussion of the MWP on some other thread, perhaps in the context of Dansgaard-Oeschger and their likely Holocene cousins, the Bond events, a subject which fasninates me to no end…

not to hijack the thread but mostly for my own clarification, can we also agree to the converse: that the existence of the physics of radiation are not evidence against long term natural oscillation?
Discussions such as this one may frustrate some, but I do feel they go a long way to clarifying what aspects of the science are clear and where and why there is uncertainty and/or a lack of clarity.
Moreover, can we acknowledge basic processes but still differ as to their relative impact, rate and magnitude of change, and, of course, our ability to adapt to the changes they invoke?

To R Gates: Yes the model is simple but the point is that it is more complete (with thermodynamics) than a model with radiation only, which is the basic model of CO2 climate alarmism based on a “greenhouse effect” from radiation alone.

I would agree that both forms, thermodynamic and radiative, need to be included in any full understanding of the climate dynamics, but specifically, when speaking to the well-established science behind the GH properties of atmospheric gases, I believe the simple thermodynamic model falls far short, and can simply not explain or predict real world effects of GH gas increases as well as a GCM’s can when considering their full LW absorption/retransmission radiative effects.

The main physical reason for the effect of GH gases is not „back radiation“ , but rather the effect on the TOA balance, which is a decreasing outgoing longwave radiation (OLR), before reaching a new stationary state.
“Back radiation” is only an internal energy flux that does not alter the energy content of the earth system. Changing OLR, however changes the energy content.

The concept of emission height or “cooling to space” together with thermodynamics/lapse rate is enough to explain the greenhouse effect. Heat transfer by radiation, latent heat or sensible heat is enough. “Back radiation” is a parameter included in heat transfer by radiation ,though.

Absorption/Reemission or “back radiation” alone cannot explain the greenhouse effect: I know that there are texts out there that try that, but they stay incomplete.
Regards
Günter

I agree that back radiation shouldn’t be invoked as the “cause” of surface and atmospheric warming. A TOA flux imbalance is required for the temperatures to change, but the mechanism by which the imbalance is transmitted by the atmosphere to the surface involves back radiation. If downward radiation to the surface didn’t increase as a result of greenhouse gas forcing and the consequent TOA imbalance, the surface wouldn’t warm.

In the context of the greenhouse effect surface and troposphere warm simultaneously because of the TOA imbalance, we have a radiative – convective equilibrium. The sun warms the surface. The net effect of longwave radiation is cooling to space, integrated across the globe.
Back radiation increases with temperature, not the other way round. Back radiation is a parameter in the energy balance of the surface, even though you can measure downwelling radiation. Downwelling longwave radiation can heat a patch of surface, if the air is warmer on top of it. However, globally integrated downwelling longwave radiation is more than balanced by sensible heat, latent heat and radiative energy from the surface. Otherwise we would not have an decreasing temperature gradient with height on average.

Back radiation increases with air temperature, and in turn increases the temperature of the surface. That is how atmospheric heating from an energy imbalance is transferred to the surface. If the lapse rate is linear, the temperature changes equally at all laltitudes. In reality, lapse rates may not always be perfectly linear, but the approximation is a reasonably good fit with observations.

It is not correct to imply that downwelling radiation only heats the surface if the air is warmer on top of it. It heats the surface even when the air is cooler, as is typically the case.

To avoid confusion about terminology, my point is that back radiation from an atmosphere cooler than the surface makes the surface warmer than it would be otherwise. The net IR flow is from the surface upward.

If the experiment you reference is the one in the link given in an earlier comment: More CO2=Less Temperature”, then you should know that this experiment, even if conducted with utmost care and precision (which I doubt), proves quite the opposite of what you’re stating. For the container with pure CO2 SHOULD BE, by the very processes you claim don’t occur, be cooler than the one with “ordinary air”, as that “ordinary air”, would, I presume, contain ordinary water vapor, and as such, with a much greater percentage of “ordinary water vapor” and would naturally show a greater GH effect (assuming of course that all the other varibles are the same).

In addition the experiment is flawed for many other reasons, for the title states “more CO2 = less temperature,” and in such an experiment one would expect to have a control container that is kept under the same conditions as all the others, and then one would expect that the only varible to change would be the amount of CO2 in a serios of other containers. One could then produce a series of data points that would show how the temperature of the container varied with the only variable being the change in the amount of CO2.

All this aside, I highly suspect that the container with “pure CO2” is indeed that, as one can see condensation on the inside, and since CO2 (under these pressure and temperature conditions) is a non-condensing gas, then that condensation is most likely water vapor, so the entire experiment is invalid as the container is certainly not “pure CO2”.

Visit the HITRAN database. Each IR emitter has a spectral signature. The temperature of the emitter vis-a-vis its surroundings is irrelevant, and in fact, the temperatures are for practical purposes identical – i.e., they exist in local thermodynamic equilibrium (LTE). The temperature of the emitter does influence the quantitative balance in the intensity of one spectral line vs another from that emitter, but the wavelength of the CO2 and H2O lines is almost completely unaltered by temperature – at least within the atmospheric range of temperatures.

Will – Using emphatic language (“Nonsense”) doesn’t strengthen a case that can’t be made. To the extent the site you link to is informative, it confirms my statement. It refers to positions, intensities, and line widths of CO2 and H2O, but with no suggestion that the wavelengths oft these molecules are shifted by temperature. Any such change under atmospheric conditions would be miniscule. If you have data to the contrary, link to it specifically rather than citing a long list of article titles.

Downwelling IR does not add energy to the system because it is energy which is already present. It does not cause net E increase.

Let us leave the subject of downwelling radiation there.

The so called “Backradiation” is the energy we expect to find from the claimed “greenhouse effect”.

The ability of a substance to absorb/emit, or radiatively transfer IR does not say anything about its ability to store that energy.

Increasing CO2, increases the radiative transfer properties of the atmosphere in the far infra-red region. How is that even remotely like a “greenhouse effect”?

How does a decrease in overall resistance of a poor conductor such as air, produce an increase in temperature? It is unphysical.

It is the opposite of reality.

“The physics of deep convection have been formulated since 1958 and are based on sound thermodynamics and measurements on location. The trends of the temperature in the high atmosphere in the last half century are very negative, starting on this height where the convection reaches. That means that more CO2 has a cooling effect rather than a warming effect.”

Imho Johnson first chapter is quite good, and is consistent with the explanation Guenter gives. Chapter 2, on the other hand, is…hum, well, it is clearly inferior to classical black body radiation, which is the most polite thing I can say ;-)

Problem is that below the troposphere, heat is exchanged by both radiation and convection (with latent heat release ), only conduction can mostly be ignored. So no simple model, either purely convective or purely radiative, is complete. However, all flux analyses I have seen show clearly that more heat is transported by convection (and a lot more when latent heat release is present) than by conduction. It follows that, if a simple model including only one heat transfer mechanism has to be chosen, better to use a convective one.

Moreover, convective lapse rate is a stability condition, so I see it (and, from what I get, classic climatology “above the atmosphere=rigid shell level” see it the same) as a limit for temperature gradient that can not be exceeded, due to stability reason. It thus makes sense that one can derive a max ground temperature from TOA temperature using this lapse rate, without knowing exactly how much the heat flux. Above TOA, we have radiative transfer, so we know TOA temperature from S-B law. Heat flux is then determined by conservation of energy, convective heat flux is just what is missing to ensure equilibrium.

The only error I see with this model is that it is too simple: 1D, and it does not take into account the fact that radiation is diffuse, so all radiation to space does not occur at a precise TOA level, it is only an average notion.

But still, compared to simple shell-like purely radiative atmosphere (1D also, all those shells and the earth are considered perfectly conductive in the horizontal directions), the model with the lapse rate is head and shoulder above: at least it does not neglect the largest heat transfer to keep only the smaller radiative one because it is tractable.

This is one of the biggest error in climatology vulgarisation: the CO2 blanket is completely wrong, but it may be enough for those allergic to science/mathematics. The radiative shell (or multishell) models are mathematically complex enough do deter those one, and thus is presented as a simple but usefull model. It is not, it is almost as wrong as the CO2-reflective blanket, and frankly, it paint a very poor image of climatology for those scientifically-minded enough to understand it, but who start to evaluate it compared to an earth-like atmosphere …

The first chapter has a major error in assigning the 10 C/km lapse rate to radiation while also referring to it as the dry adiabatic lapse rate. Radiation has nothing to do with the 10 C/km dry adiabatic lapse rate. A radiative equilibrium is isothermal, not isentropic. This mess confuses the whole later argument about lapse rates.

First the Bad news
…….”a major error in assigning the 10 C/km lapse rate to radiation while also referring to it as the dry adiabatic lapse rate. “……

The dry adiabatic lapse rate is given by dT/dh = -g/Cp
=-9.8K/km
Where g = Gravitational Field Strength
Cp = Heat Capacity.
In other word the temperature acquired by air molecules after contact with the surface drops by almost 10K per Km of ascent.

Now in the case of the dry adiabatic troposphere although water vapour may be absent, CO2 being well mixed should be there as usual.

However it seems to play no part that I can see.
Even more alarming, in this Nasa description of the atmosphere with various conditions specified there is no mention of greenhouse gases!
Surely the radiative effects of CO2 must get at least a tiny mention, shouldn’t they?

Now the good news
The greenhouse theory has been banished to the TOA.
The radiative gases radiate long wavelength EM radiation to space to attempt an overall radiative balance for the Earth.
It acts like the drain hole at the bottom of the bath.
The Sun acting like the water flowing from the bath taps.
If the drain hole is too narrow, water level rises(temperature); if too wide temperature falls.
Now back to a dry atmosphere; the temperature lapse rate will still fall at 9.8K/km in the troposphere.
The net effect then of changing CO2 and H2O vapour is to move the tropopause up and down.
Now this truncated version of the Greenhouse Theory is one that I think is very plausible.

In some way we can agree that the tropospheric lapse rate is fixed by the dry and moist adiabatic lapse rates, and therefore its whole temperature profile is linked to the surface temperature, which is in turn affected by a radiative balance. CO2 can’t change the lapse rate, which is based on physical constants, such as g, cp, latent heat constant, gas constants, etc., but can only affect the surface temperature to raise the effective radiating level of GHGs. The troposphere’s only degree of freedom is the surface temperature in this simplified model that represents CO2 effects in one atmospheric column.

The lapse rate is determined by thermodynamics of moist air as long as there is a sufficient heat flow from the surface to the upper atmosphere to keep the real lapse rate at the adiabatic limit. That requires that the surface is warm enough to release the required amount of energy excluding that part that escapes through the atmosphere without being absorbed. The heat flow is a combination of radiative transfer, convection and advection of latent heat. Convection is the part that guarantees automatically that the temperature gradient cannot exceed the adiabatic lapse rate. Therefore the strength of the radiative transfer does not influence the result as long as the surface is warmed so strongly that the adiabatic lapse rate would be exceeded without convection.

Adding CO2 influences the situation in at least two ways. The first is due to the reduction in the amount of energy that escapes without being absorbed. Due to this effect less energy is leaving directly from the surface. The same applies also to the low clouds. In equilibrium all this reduction must be compensated by increased radiation from the upper atmosphere and increased heat flow from the surface to the upper atmosphere.

The second effect occurs around tropopause. The increased CO2 concentration moves the effective radiating altitude of CO2 higher up.

Combining both effects we notice that the radiation that escapes from the upper atmosphere must be both stronger and originate higher up. Both requirements lead to an increase in the temperature of the atmosphere at a fixed altitude if upper troposphere near tropopause. The two effects are separate. The first comes from the increase of CO2 at lower altitudes, the second from its increase at tropopause. My understanding is that the first effect is stronger than the second, but I have not done any calculations to support this conjecture.

Pekka
Look at a description of the broad outlines of the atmospheres structure with particular emphasis on the troposphere.
There is no mention of the greenhouse effect.
The effect of water vapour is explained through the mechanism of latent heat.
Of course CO2 and H2O radiate in the IR.
It just doesnt seem to be that important.http://rst.gsfc.nasa.gov/Sect14/Sect14_1b.html

Bryan
That is a description of certain issues. That something else is not mentioned there is not an argument against that. I didn’t notice anything there that would in some way contradict what I wrote here or in numerous other messages on this site.

It is also dishonest to pick one sub-chapter from the tutorial stating that it does not discuss greenhouse effect when the previous sub-chapter does discuss it. I think you might try to avoid being dishonest.

I have no way of knowing how honest you are but I give you the benefit of the doubt.

I was genuinely surprised when I came across the NASA document.
Beforehand I would have thought that the radiative effect of CO2 would have to be accounted for even in a dry adiabatic Earth atmosphere.
In fact it would be a good experimental method of isolating the CO2 effect from the H2O effect in the limit.
There seems to be a growing body of opinion that the radiative effects of CO2 are either minor or self cancelling.
A number of IPCC advocates are now promoting this and say the real and significant greenhouse effect is to be found at TOA.

To put it simply, CO2 affects the absolute temperature, not the lapse rate in a dry atmosphere. This is why it is important. It displaces the whole temperature profile according to its radiative effect.

Bryan,
I have become less polite to you after your baseless insulting comments towards me some times ago.

I told you that the previous sub-chapter of the same tutorial tells that the CO2 is important. Why do you neglect that and choose to concentrate on the next, which discusses other things.

If you find the chapters contradictory, the fault may be in your understanding of the content and its significance. For that the only help comes from studying the basics. Trying to make guesses from more advanced texts (even when they are tutorials like in this case) leads often to such misunderstandings that are visible on this site all the time.

Jim D
I think we are in close agreement about the broad outlines.
On the dry adiabatic atmosphere I used to be a bottom up advocate.
Surface temperature determined by Sun/Earth interaction.
Gravity giving rise to lapse rate of 9.8K/km.
This very simple structure then modified by convection, latent heat and radiative effects till the convective impetus petered out at the tropopause.
Above the tropopause the radiative effects adjusted to keep the Earth energy in/out in balance.
However recently I find the top down approach quite compelling.
The TOA conditions acting like a gate.
The consequences of the gate being too narrow being passed back down by the same dry adiabatic lapse rate to determine the surface temperature.

Pekka
I’m sorry if I addressed you in a way that you found disrespectful.
I think I used the word IPCC apologist rather than my usual term IPCC advocate so I must have been loosing my cool.
I think that one undisputed plus for Judith’s site has been to tone down the insult level.
However if you are a sceptic you have to develop a much thicker skin.
For a laugh go onto a site like Deltoid and pretend to be Nasif Nahle.
You wont get out alive!

Bryan,
The net discussions are often difficult. Short messages cannot always transmit the tone correctly. Some of the participants are provocative by purpose, and some others write claims that they know to be false, even deliberate lies.

In climate science and in particular in the physics behind the climate science there is very much that I have full confidence in based on my schooling and understanding based on that. There are many other things I have much less confidence in and also conjectures that I consider more likely to be false than true.

In these discussions I comment most often on issues I am certain about. Trying to do that as well as I can and getting answers that show no evidence on willingness to learn, is often frustrating and leads to doubts about the goals and even honesty of other participants. All concrete hints to the same direction strengthen these suspicions. At the same time I know perfectly well that many points are difficult and cannot be verified personally without specialized education.

I try to stay polite, but sometimes it leads to a point, where I start to think that I am played with and that I am making fool of myself unless I react strongly. I know that this is going to happen also in the future, if I continue to comment on climate sites.

Bryan, I think the dry adiabatic atmosphere can be thought of from both perspectives, top and bottom, which both lead to a requirement that the whole temperature profile is displaced in the warmer direction when CO2 is added.
My view is that more CO2 initially reduces outgoing IR but also causes the surface to warm, which in turn convectively forces the atmosphere to warm, increasing the outgoing IR till it balances again.

I just came across this discussion, and since it was a discussion rather than an argument, I thought I would offer my perspective. In general, a TOA radiative imbalance due to impeded loss of IR to space is translated into more energy at each layer, ultimately impacting the surface temperature. In turn, this further warms the atmosphere over time as the surface temperature rises. The immediate result of atmospheric warming is an increase in lapse rate beyond the adiabat due to greater warming at low than at high altitudes. This results in static instability that triggers a convective adjustment restoring an adiabatic profile (which in most regions eventually proves closer to a moist than dry adiabat due to latent heat transfer with release at higher altitudes).

The radiative changes are very rapid. The dry convective adjustment (according to Andy Lacis) is slower, and the full change including the latent heat effects occurs over many days or longer.

The “super-adiabat” would tend to enhance surface warming because of the higher lapse rate. On the other end, the moist adjustment creates a negative lapse rate feedback that reduces the warming effect. This, however, is accompanied by a positive water vapor feedback, and the combined water vapor/lapse rate feedbacks are generally computed to show a net positive effect.

Nobody claims that there would be warming in the sense you imply – nobody at least of people supporting main stream climatology. Therefore there is absolutely no need for such a hot spot.

This is not in contradiction with the fact that atmosphere radiates to surface and contributes to a temperature increase. If you do not understand the point after all these discussions and hundreds of messages where it has been explained in different words, then I propose looking in the mirror.

you are a very reasonable, intelligent, respectful person. I respect you for your knowledge and comportment. Unfortunately I am often none of the above.

Frank started discussing heating at elevation which is caused by bottleneck in IR emissions. He did not give a mechanism for the purported bottleneck. He also talked about heating from the top down.

With emissions bottlenecks, heating from top down, backradiation, and eventual heating of the surface, exactly what am I supposed to assume he is talking about??

I have actually read explanations of this effect and have always been confused about how the bottleneck comes about. The statements seem to say that the heating will raise the effective emission altitude as the heated atmosphere expands. As the new higher altitude is supposed to be cooler than the old average altitude less IR can be emitted.

Hopefully you can clear this up for me. If the atmosphere expands from warming, doesn’t that say the higher altitude will be about the same temperature as the old altitude? That is, the altitude will average higher but the temp will be about the same because everything is warmer.

If we are saying that this warming will not happen it would seem to me that the temperature is more controlled by the lapse rate and convection, in which case there will be no significant warming in the first place without major perturbation.

Thank you for any clarification you can give on this “hot spot” issue.

kuhnkat,
Nobody of us is capable of always finding clear expressions for his messages. While many issues are not really complicated, they involve anyway numerous details and attempts to explain the issues in limited space and simpler language requires leaving something out. All too often happens that just those things left out are for some reason in the mind of the other party of discussion.

Another problem is that the concepts are not defined precisely. What means “warming a body”? In these discussions some participants expect that the effect that warms must be the final source of heat or energy that rises the temperature to its final value. A colder body can never do that for a warmer one.

Many others mean by the sentence “body A warms body B” that taking the A away would lead to a colder B. This is very often possible even when A is colder than B, if B is heated also by some other source. I have still difficulties to understand why this second way of interpreting “A warms B” is not understood by everybody.

I commented to the most recent post of Judith that many people can much better form general views on issues than present scientific type arguments in their support. It is very common, that the role of detailed arguments is overvalued. They are overvalued often both by those who are competent in presenting them and by others for whom a more general intuition works much better.

This is also a source of dispute and confusion, when people are sure that they are right in the main issue, but cannot justify it by a detailed arguments. There is too much belief that detailed arguments are the way of winning argumentation, even when that does not work at all. In climate issues this fact comes up all the time. Even for experts a more general and intuitive approach may give more reliable results than trying to prove by detailed arguments when not enough is known about those details.

Judith,
I want to comment that I am increasingly an admirer of your approach, especially on this technical thread.
By letting others take a turn at being the authority, people seem to come to more openly examine their own ideas and knowledge – including errors. By just minding the store, wrong assumptions and weak knowledge claims are brought to the surface by others, instead of driven underground by your authority. It’s a better learning process than confrontation.

To complement the many comments made above indicating that the radiative transfer principles contributing to the greenhouse effect, including the role of back radiation (downwelling longwave radiation) are consistent with the laws of physics, it’s worth pointing out that the back radiation predicted from these equations has been confirmed by measurement. For a general overview, readers should revisit the Radiative Transfer Models post to review the links Judith Curry has cited, with particular reference to the Atmospheric Radiation Measurement (ARM) program – the post is at Radiative Transfer

For a particularly informative description of the ARM program, see –ARM Prrogram

You write:
“Let us now sum up the experience from our analysis. We have seen
that the atmosphere acts as a thermodynamic air conditioner transporting
heat energy from the Earth surface to a TOA under radiative heat forcing.
We start from an isentropic stable equilibrium state with lapse rate
9.8C/km with zero heat forcing and discover the following scenario for
the response of the air conditioner under increasing heat forcing:
1. increased heat forcing of the Ocean surface at low latitudes is balanced
by increased vaporization,
2. increased vaporization increases the heat capacity which decreases
the moist adiabatic lapse rate, if the actual lapse rate is bigger than the actual moist adiabatic rate,
then unstable convective overturning is triggered,
4. unstable overturning causes turbulent convection with increased heat
transfer.
The atmospheric air conditioner thus may respond to increased heat forcing
by (i) increased vaporization decreasing the moist adiabatic lapse rate
combined with (ii) increased turbulent convection if the actual lapse rate
is bigger than the moist adiabatic lapse rate. This is how a boiling pot of
water reacts to increased heating.:”

I think your model is incomplete, since the “heat forcing” as you name it is external and you describe only energy flux that is internal. “Heat forcing” increases the energy content of the earth system and therefore leads to increased temperature on the long run to decrease your so-called “heat forcing” by increasing outgoing longwave radiation (OLR). Your model leads necessarily also to increased temperature. You describe radiative-convective equilibrium as well. So what is different in your model compared to the classical model
Best regards
Günter

One thing that always puzzles me when IR and the GHE are discussed is why on a nice clear summer day in Atlanta I don’t melt. I mean, we supposedly have an AVERAGE downwelling radiation of 324 wm-2. I would imagine that the downwelling radiation at noon on a humid day in Atlanta would be higher than the average due to all the water vapor in the air. Let’s make it 25% higher, or 405 wm-2. Now, let’s add the sunshine, which is certainly greater than 900 wm-2 at noon. So we now have 1305 wm-2 on my greybody. Using the SB equation, with emissivity of 1, that translates to 116 C. Something doesn’t add up.

Hi Jae… Excelent observation! You could calculate the energy the human body would absorb, from those 405 W/m^2, by knowing that it has an average absorptivity of 0.7. Imagine the hard work the body would perform for getting rid of that excess of energy!
Regards,
Nasif

A black body radiates 400 W/m^2 at a temperature 0f 17 C. It’s the sunlight that would cause a problem for an object unable to shed heat via perspiration, reflection, conduction, or respiratory heat loss. With 900 W/m^2 absorbed, its temperature would equilibrate at 82 C.

At an ambient temperature of 40 °C, a normal human body absorbs 43.4 W. That figure represents an intensity of 160.71 W/m^2. However, Jae mentions c.a. 1305 W/m^2 the energy emitted by the atmosphere, if the stuff of backradiation were true. Fortunately, as Jae points out in his post, it’s not true because, if it were true, the human body would absorb the dizzying amount of 913.5 W, which would represent an intensity of 3,383 W/m^2.
On the other hand, if you are considering an idealized blackbody emitter, emitting 400 W/m^2, then the human body would absorb 280 W, which corresponds to an intensity of absorption of 1,037 W/m^2.
Now, let’s consider a blackbody-ambient at 17 °C; the human body would be losing, not gaining, 23.17 W (-23.17 J/s), which corresponds to -85.82 W/m^2.

Your figures aren’t well explained. The average human has a surface area of about 1.7 m^2, so I’m not sure what you mean when you imply that 160 W/m^2 corresponds to 43.4 W absorption.

More importantly, an ambient temperature of 40 C is very hot (and represents much higher than average back radiation). It is equal to a Fahrenheit temperature of 104 F, which is very difficult for humans to tolerate on a sustained basis, although they can adapt temporarily through sweating and panting.

It is incorrect to state that 1305 W/m^2 is emitted by the atmosphere. Most of that figure comes from the assumed value of 900 for sunlight, which would be an immense problem for an individual who could not adapt, and would be unsustainable for any extended period. Back radiation has little to do with it.

Finally, in the example I gave, which you cite, of ambient temperature at 17C, this is easily tolerable, because human metabolism generates enough heat to compensate for the heat loss. In fact, tolerable climates for humans require some degree of heat loss to the environment, because we can’t shut down our metabolism, and so if we couldn’t lose heat, we would quickly die.

In essence, the values I gave in my earlier comment are correct, and the most significant problem in the cited example is the sunlight.

Fred:
“It is incorrect to state that 1305 W/m^2 is emitted by the atmosphere. Most of that figure comes from the assumed value of 900 for sunlight, which would be an immense problem for an individual who could not adapt, and would be unsustainable for any extended period. Back radiation has little to do with it.”

I originally thought you digged the conversation, bro., but it appears that you don’t have a clue!

Dear Fred,
Corrections:
0.27 m^2 exposed to radiation, unless it is naked.
40 °C is a usual temperature, here, during summer.
The average absorptiviy of the skin, in a normal human being, is 0.7.
I never said you’re wrong. I only made the calculations for the conditions you specified in your post. At 17 °C the human body would lose 23.17 W of energy, which would be transferred to the environment. It would be a problem if we were endothermic organisms. Fortunately, we are self-regulating thermodynamic systems; otherwise, we should spend many hours under the sunbeams, as lizzards, for example.
Now, if you say that a blackbody at 17 °C is emitting 400 W of thermal energy, how much Watts it would emit in my location when the temperature can reach, easily, 40 °C in summer?

Nasif – A true black body at 40 C (313 K) would radiate about 544 W/m^2 in accordance with the SB equation.

Humans can’t afford to sustain a body temperature of 40 C for very long. At 37 C body temperature, they lose heat by all the mechanisms I mentioned above, not just radiation. I’m sure humans can tolerate an ambient temperature of 40 C for intervals, but I doubt they can tolerate it for a very long sustained period, day and night, without some exogenous cooling source, such as drinking cold water.

Dear Fred,
Exactly! An idealized blackbody at 40 °C would emit 544 W/m^2, which is not the case if we consider the real system atmosphere-lithosphere. The external operator, for the case of my location, where we undergo up to 40 or higher degrees Celsius during the summer daytime and 30 or more degrees Celsius through the nighttime (and, believe me, we have survived it through many days), cannot be other but the Sun, and you will agree on this because the atmosphere cannot “store” such load of heat. Primarily, because the absorptivity of the whole atmosphere, including a 4% of water vapor, is quite low (by the order of 0.01 when considering the mean free path length of photons and the time they spend to leave the Earth’s atmosphere). That’s why, I sustain that the current models on TAO (or TOA) are absolutely flawed.

I’m not sure what your point is. The emissivity of the atmosphere in the IR range of greenhouse gas emssion and absorption is certainly less than unity, but although the emissivity of any small atmospheric layer, even near the surface, is small due to the low concentration of greenhouse gases, the total downwelling longwave radiation comes from multiple layers and is substantial.

Radiative transfer codes derived from the Schwartzhcild radiative transfer equations, in conjunction with observed values of CO2, H2O, and surface temperature, yield values for both OLR and downwelling radiation that match observations very well, confirming the validity of the principles on which they are based.

Fred… I’m referring to the time that a photon takes to abandon the atmosphere, as wide as it is, and to the distance that a photon can travel without touching a molecule air, those molecules that can absorb it or scatter it. From the databases of both parameters, we find that the air, as dense as it is, we find that the emissivity of the air, 4% of water vapor included, is 0.01; no more. The atmosphere is not a blackbody.
Perhaps those observers on the downwelling radiation are observing other things, except any downwelling radiation?

Here is the reductio ad absurdum. A human body is like a black body at 37 C which emits about 525 W/m2. Now according to this theory proposed above, nothing can emit towards a human body that isn’t as warm as it, so when you go out at night you are losing heat at 525 W/m2. Wouldn’t you cool down really fast even on a balmy night with a 20 C ground temperature?
The fact is, everything emits towards everything else regardless of relative temperature. We do have incoming radiation to us at night even from the cooler ground. Go out and try it. Explain how this is different from the atmosphere radiating towards the warmer ground.

Wow! Jim! You have got rid of S-B Law! Please, tell me, are you related in some way to the Hockey Stick producers? Besides, you made us, humans, real blackbodies!
Jim, a human body has a temperature of c.a. 37 °C. If it (the human body) is exposed to an environment at 17 °C, it would lose 23.17 W, i.e. the energy transferred by radiation from the human body to that environment at 17 °C, according with the S-B Law derived formulas. No more. The formula is quite easy:
Q = e (A) (σ) (Te^4 – Thb^4)
Where e is the emissivity of the system (human body in this case), A is the area exposed area of the human body, σ is Stefan-Boltzmann constant, Te is the ambient temperature in K, and Thb is the average temperature of a normal human body.
Go on, make your calculations.

Jim…
I’m not having the air radiating towards the body, but quite the opposite. The body is losing energy, not gaining it from the environment. Under those conditions, the body is pushed to generate more thermal energy, from metabolism, to maintain his energy state in a quasi-stable state.
In summer, only when the environmental temperature is higher than the body’s temperature, the body gains energy from the environment; however, the thermoregulating system starts working to get rid of the excess of thermal energy absorbed.

If you applied the S-B formula correctly, you had to obtain a negative result, which means that the body is losing energy, not gaining it; the body must generate more energy through the cellular respiratory process and other mechanisms for not cooling off, in this case.

The Te term in your equation comes from back-radiation is all I am saying. If you believe your equation, you implicitly agree with back-radiation. I am not saying your equation is wrong, I am saying it proves back-radiation exists.

Q = e (A) (σ) (Te^4 – Thb^4)
Where e is the emissivity of the system (human body in this case), A is the area exposed area of the human body, σ is Stefan-Boltzmann constant, Te is the ambient temperature in K, and Thb is the average temperature of a normal human body.

It’s the energy from the human body to the environment… Have you noticed that the energy flows ALWAYS from the warmer system to the colder system? Backradiation doesn’t apply because it is the human body what is radiating, not the environment.

Again, for this case, the human body is LOSSING energy, NOT gaining it.

No, Thb is from the body to the environment, Te is from the environment to the body, which is why they have opposite signs. Since the environment is colder than the body, this is the term the slaying book says should be zero. We clearly agree the book is wrong on this matter. The environment is preventing the body from losing heat at an unrealistic rate of 525 W/m2 in the same way as the atmosphere prevents the ground from losing heat at an unrealistic rate (where a similar formula applies with Thb being from ground temperature, Te from the atmosphere).

I’m afraid it’s you who’s confused Nasif, the environment radiates according to its temperature and the body absorbs it, the body also radiates according to its temperature. The net effect is that when the body is warmer than its surroundings the body loses heat (when the environment is hotter than 37ºC the body gains heat).
The environment doesn’t stop radiating because the warmer body is present, ‘back radiation’ is always present. that’s what the term, e (A) (σ) Te^4, represents.

Nope, confusion is on your side. I’m afraid you think the environment is never colder than your body. The formula is the S-B equation, and you’re blatantly misinterpreting and twisting it, as usual in AGW idea.

Phil, you’re absolutely wrong. If you eliminate the term Tb^4 from the formula, you would be referring to the energy of the atmosphere. It has nothing to do with “energy received from surroundings”. You have only one term, the temperature of the environment, and it is the result of the FLOW of energy IN the environment.

To Phil…
Anser this question for me: what the value of “e” could be in the formula that you say it is “energy received from surroundings”? If you are referring only to the temperature of the air, then you have to introduce the value of “e”, and in the case of the human body, you have to introduce the value of “e” for the emissivity of the human body.

It’s very simple. You’ve dissected the formula and you’re referring to two different things.

jae, absolutely correct. Another simple example of how the purely radiative calculation as proposed by Pierrehumbert and other climate scientists gives completely the wrong answer. The correct answer of course, is that you need to take into account other mechanisms of heat transfer such as convection and evaporation. This point has been made dozens of times on all these threads.

There is convection etc, within the Earth’s atmosphere, but the only way that heat (energy) is released from the Earth to outer space is through radiation. Reflection of incoming solar radiation by clouds is the big question. Until someone can accurately define how this changes the amount of incoming energy, predictions of future temperatures cannot be accurately calculated.

Your question is somewhat off-topic, but relative humidity has not increased over the past century, while CO2 has risen almost 40 percent over its pre-industrial concentration. Water vapor, in fact, has such a short atmospheric lifetime that its absolute humidity value cannot remain elevated in the absence of some other factor that causes the atmosphere to warm and thereby retain more water. That is why it operates as a feedback mechanism amplifying warming mediated by CO2, solar increases, or other forcings rather than acting as a forcing in its own right. If the average relative humidity had in fact increased by 300 percent, the warming would have been immense.

I believe this has been discussed in the threads on feedback and on climate sensitivity. You might want to review the previous discussions before proceeding further, so as not to repeat material already covered.

Water vapor, in fact, has such a short atmospheric lifetime that its absolute humidity value cannot remain elevated in the absence of some other factor that causes the atmosphere to warm and thereby retain more water.

Note: this is a technical thread, please keep your comments focused on Johnson’s arguments, or other aspects of Slaying the Sky Dragon. General comments about the greenhouse effect should continue on the Pierrehumbert thread.

Now that we have aired some stuff, I agree that the discussion is best left to those with a degree in physics (maxwell, pekka, and there are others among the denizens of climate etc that have not shown up).

..could you help me out by relating what you say directly to the topic at hand, and how the two connect?

THE POTENTIAL DEPENDENCE OF GLOBAL WARMING ON THE RESIDENCE TIME (RT) IN THE ATMOSPHERE OF ANTHROPOGENICALLY-SOURCED CARBON DIOXIDE
by Robert H. Essenhigh, Department of Mechanical Engineering, The Ohio State University, Columbus, USA. In press in the journal ‘Energy and Fuels’, but now available at ACS website http://pubs.acs.org/articlesonrequest/AOR-fAEJXMX3JgkNFmgAkdpu

Derry… The residence time of carbon dioxide in the atmosphere could be as long as you wish… The important thing here is that the lapse time for the thermal energy to stay in the atmosphere is quite low: 0.0097 milliseconds! The mean free path lenght of one photon of thermal energy is 21 m. Besides, from experiments realized by many physicists, at its current concentration in the atmosphere and under the current physical conditions of the atmosphere, the carbon dioxide cannot absorb-emit more than 0.002 of thermal energy.

The bottom line in all this is that there is absolutely no proof–or even a reasonable demonstration–of an “atmospheric greenhouse effect.” All planets/moons with an atmosphere have a surface temperature that is much higher than the SB equations–based on the IR from those bodies–at about 100 mbar–suggest. It is high time that the “climate science community” HONESTLY faces the questions that are posed by the skeptics (and stop with the dishonest, unconvincing, meaningless, disgusting, and typically liberal insult of “denialists). The “community” has already lost the public and only has politicians and rent-seekers on its side. The smart ones are already publishing papers refuting the stupid, ever-present “catastrophe” of our times (aka, Chicken Little). Grow up!

Fred Molten,
one can make an interesting thought experiment about “back radiation”.
Let’s assume we have the earth system as a stationary state with 280 ppm CO2, well mixed. Normal lapse rate.
In the first case, we bring in a thin layer of CO2 that contains a similar amount of CO2 compared to the whole atmosphere in a thin layer next to the surface.
In the second case, we bring in a thin layer of CO2 that contains a similar amount of CO2 compared to the whole atmosphere in a thin layer next to the top of the atmosphere.
Both layers are equilibrated with respect to temperature.
“Back radiation” is highest in the first case, but surface temperature is lowest. It is the emission height that counts.
As I said, it is the cooling to space that rules. That is, why I don’t think “back radiation” is a necessity to explain the greenhouse effect.
Best regards
Günter

I don’t believe there is any way to warm the surface without back radiation. In its absence, radiative imbalances in the atmosphere would change atmospheric temperature but not surface temperature (except for the minimal effects of conduction).

Regarding your thought experiment, my assessment is the following, at least at first consideration. If we ignore water vapor as well as non-radiative phenomena, I believe that the same number of CO2 molecules will absorb the same number of photons, regardless of altitude. At equilibrium, they will emit as much energy as they absorb, and the temperature of that layer will therefore rise until it suffices for that emission to occur. For the high altitude case, this would cause a temperature inversion such that temperature is much higher at the height of the absorbing layer than it is below. This is clearly an unphysical situation, but something vaguely similar occurs in the stratosphere, where ozone absorbs solar UV, resulting in a temperature inversion.

There may be other factors that I’m ignoring in addressing your thought experiment, but my first paragraph rather than the second is what I would emphasize – the surface can’t warm unless it receives the radiation needed to warm it.

There is only one way the physics really works, but there are many ways of putting this into words and more than one way of formulating the equations used to calculate the correct results.

There are no limits on the number of ways the physics can be misrepresented and we have already seen pretty many in comments on this site. Countering these erroneous claims is made more difficult by the fact their details may well be in agreement with some of the correct descriptions while the errors are in putting these pieces together. Some of the erroneous theories are pure nonsense from start to end, but not all of them.

There is a continuing argumentation on whether one mechanism can heat an object which is actually receiving heating through many processes or from many sources. Then one may claim that any single process cannot heat it, if the processes are individually weaker than cooling of the object. Such arguments are presented as if all heat sources would not add up whatever their mechanism is and as if each of the heat sources would not have its share in the total heating. How can this kind of argumentation be supported by so many?

Your statement that “back radiation” is fictional, a figment of the imagination for any length of time longer than a fraction of a second, I totally agree. I will read your paper (book) as I get time and I might not totally agree with the methods you use to describe this. Maybe so.

I have always viewed “back radiation” as a null operator:

— 2 units or energy leaves a surface cooling the surface by that 2 units.
— That 2 units are absorbed by molecules (GHGs) warming the gases locally.
— 1 unit of energy is radiated to space and lost to the system and also cooling the gases by 1 unit.
— 1 unit is radiated back to the surface to be reabsorbed warming the surface by 1 unit and also cooling the gases by 1 unit.

— NET EFFECT: In the end the surface has cooled by 1 unit and 1 unit is lost to space, all in a few milliseconds.

All other effects have totally cancelled. One way to view this is a reduction of effective emissivity of the surface by at factor near one half.

That seems very close to your initial statements I was reading and I agree, there is no real warming. After reading onward I may not agree with the exact methods you use to place this effect into a physics framework but I will read it, that takes time.

Yes, Wayne, but if the surface was at a temperature that demanded it radiate 2 units and it only radiated a net 1 unit, then it is not in equilibrium anymore and its temperature must go up. (I think I got that right, I normally lurk on the technical threads and keep my head well down!) Regards, Rob

I started to write you a detailed explanation, but after reading many of your comments, I’m afraid it would be pointless if you are not able to take my example above and limit it the exact case I gave. The two units must be radiated upward, those two are not all radiated upward (your injection of temperature), and those two units must be absorbed and not transported directly to space without absorption (window).

If you can not grasp even that simple example there probably is no hope of you understanding Dr. Miskolczi’s methodology he used in his latest papers and which is very close to my example above.

Kind regards. I like to lay low too. Open your mind, the AQUA AMSU temperature just hit the same temperature that was read thirty years ago, how can that be? If I were you I would get real curious right now. I have already found my answers.

This is the clearest explanation for non-specialists like me that I have ever come across. I’ve saved it to my hard drive.

I have a question. Spencer says that with no atmosphere, the earth’s surface would be around 0 deg. F (-18 deg C or 255 deg K). Suppose all GHGs (but nothing else) were removed from the earth’s atmosphere (I’m assuming there would be no water on the planet). Would the temperature be greater than 0 deg. F?

I’m hoping that’s on topic, because I’m trying to establish in my own mind whether just the presence of an atmosphere pretty much as dense as the one we have now, but sans GHGs, would in some way produce warming. I hope it makes sense to ask the question.

afaik, yes: what I think would happen is that all radiation would occur at the surface, because the atmosphere would be perfectly transparent for all wavelength, at by K., would also emit no EM radiation (In reality, it would not be like that, but I guess it is the idealised situation you have in mind).
So, the surface T at equilibrium would be computed the same as in the no-atmosphere case.
But I am not so sure about the T profile in this transparent atmosphere. Quite fast, we should reach the lapse rate for this gravity field and adiabatic fluid, by convection. I think, after some time, conduction should produce uniform T, which seems to be the no -heat flow limit regime (well, assuming 1D problem)… but I am not sure uniform T is the equilibrium in a gravity well, some equirepartition principle may mean that T goes down the higher you go (some interpretation of virian theorem would say so too, which makes sense: monoatomic gases modeled as elastic spheres, should have a lower velocity at top of atmosphere…else they would reach escape velocity) which would falsify simple conductive transfer, except if “total” temperature incorporate somehow potential energy. Interesting question, I would be interested about what gaz kinetic theory specialists would have to say about that, all in all my hinch would be for non-constant T and conduction process acting with a “total” T incorporating potential energy….

yes, definitely a non-constant T at equilibrium due to gravity: after all, simple heat transfer linearly proportional to T gradient is not a fundamental law, it is derived from kinetic gas theory, one of the hypothesis being, iirc, no volume forces. Gravity is a volume force, so I am almost sure the Fourier law for conduction is not strictly valid in this case (it is a first order phenomenological law, nothing fundamental there), but that heat transfer must incorporate gravitational potential energy…..

Yes the convective equilibrium lapse rate is g/cp, about 10 K/km, so I would expect something like that. It is complicated by variations in surface heating with latitude and the diurnal cycle, so it is not clear what temperature this would equilibriate to over the surface, but since the non-GHG atmosphere has no other cooling mechanism than contact with a colder surface, the surface temperature would somehow control its eventual equilibrium temperature profile.

“I have a question. Spencer says that with no atmosphere, the earth’s surface would be around 0 deg. F (-18 deg C or 255 deg K). Suppose all GHGs (but nothing else) were removed from the earth’s atmosphere (I’m assuming there would be no water on the planet). Would the temperature be greater than 0 deg. F?”

Michael – Removing only GHGs would have slightly greater cooling effects than removing the entire atmosphere. This is because atmospheric molecules (O2, N2, CO2, etc.) scatter some sunlight back to space, and in their absence, all solar radiation would reach the Earth’s surface.

The 255 K figure assumes no other changes. In fact, in the absence of water, there would be no ice, snow, or clouds, and the Earth’s albedo (percent of sunlight scattered or reflected back to space) would decline significantly. As mentioned above, some scattering would still occur from air molecules, and some from light-reflective surfaces such as sand, but it would be far less than the current 30 percent figure. As a result, the Earth would absorb more heat, and warm well above 255 K. I don’t know what the exact temperature would be. It would be colder than today, but probably by only a modest amount.

A small correction – Above, I should have omitted CO2 from my example of light-scattering molecules, because you were asking what would happen if it were removed. Of course, N2, O2, argon, etc., would remain, and their contributions would be little diminshed by the removal of a minor constitutent by volume such as CO2.

To summarize my position:
1. Radiative heat transfer is carried by electromagnetic waves described by Maxwell’s equations. The starting point of a scientific discussion of radiation
should better start with Maxwell’s equations than with some simplistic ad hoc model like the ones typically referred to in climate science with ad hoc invented “back radiation” of heat energy. If there is anything like “backradiation” it must be able to find it in Maxwell’s wave equations. In my analysis I use a version of Maxwell’s wave equations and show that there is no backradiation, because that would correspond to an unstable phenomenon and unstable physics does not persist over time.

2. Climate results from thermodynamics with radiative forcing, and radiation alone cannot tell anything of real significance, such as the effect of changing the atmospheric radiative properties a little: It is not clear if more clouds or
water vapour will cause global cooling or warming, or the effect of a small change of CO2. Climate CO2 alarmism is based on a postulate of a climate sensitivity of + 1 C which is a formality without known real significance.

2. Agreed. And I am not too comfortable with the model hierarchy used in Climatology: pure radiative models are imho correct,but they do represent the main heat transfer in earth system well…so are useless for earth. TOA+lapse rate is better, but I think they are not so solid mathematically, I do not really like the treatment of it. Should be consolidated, and then it is 1D, so predictive value is not clear, but at least this model could have heat transfer similar enough to actual heat transfer on earth to be somewhat useful.
Finaly, there are GCM….but they are huge, use numerical methods I do not like (FD for something with complex continental shapes – yuck), and introduce a lot of approximation (solving NS equation on earth lenghtscale is ridiculous…so it is not NS that is solved, but some kind of approximation of it. Never really have seen the PDO that are solved in fact, which is in itself very worrying. Lot of blackboxes modelling different process connected to each other (radiative module – ocean module – salinity module – biological C cylce module), so it is more an ad-hoc model that something starting from first principles or even a solid set of PDO. OK, not easy to do better, but the validation is pitifull for this kind of model, which live and die by extensive validation.

1. Not agree: Maxwell’s equation are ok, but you need quanta (or a replacing full theory) to deal with radiative heat transfer: It is not even needed to accept black body treatment by Plank to know Maxwell alone will not be up to the task: those EM are radiated by molecules, that can not be modeled by
maxwell: remeber the paradox for Bohr atom model of orbiting electrons? Why does the electrons not fall down in the nucleus, when all its kinetic energy should be dissipated by bremstrhallung/synchrotron radiation? This was a fundamental problem (before or at the same time as BB radiation) that was solved by quantization. You may not like Quantum mechanics (I myself have trouble with it, it seems like an unfinished and overly complex theory), but it is extremely successfull, maybe the biggest success of physics. Going against it is a huge task, there is a reason it was accepted between the wars although it is quite often counter-intuitive: it explains and predict a lot, much more than simple BB radiation.

By the way, you continue to mention that backradiation would be unstable. A few posts (some of mine too) challenged this. You still not have explained why you believe it would be unstable, just that it is and is a flaw of S-B model. This is not a tenable position, you need to show how S-B is unstable and how your theory is not. Good luck!

Maxwell equation are valid for propagation. For emission/absorption, you need to take into account the quantitized nature of emmiters/absorbers when those emitters are molecules or atoms. Which is the case for the IR wavelength of interest. If you want to use continuous Maxwell down to atomic lenghtscale and energies, you predict unstable atoms. Everything should go back to neutronium, which will be a problem for predicting EM radiation with Maxwell equations ;-)

Actually I believe that it is possible to describe the situation without the need of standard way of introducing the quantization. The quantum field theory of electromagnetism (QED) is used in practical calculations as perturbation theory in the form of Feyman diagrams, but this is not necessary in principle. Similarly the quantum transitions of molecular states are introduced in the spirit of Copenhagen interpretation of quantum mechanics. This is again not necessary while very useful in practice.

Both choices are valuable practical tools in quantitative physical analysis, but they are not really required. In principle one can formulate the whole problem by writing the full equations to describe all molecules in the atmosphere and all radiation by Schrödinger equation and Maxwell’s equations and possibly introducing modifications related to QED. There is no basic reason to assume that these equations cannot be used in another way, which does not involve the traditional way of quantization at micro level but aiming directly to answering some macroscopic questions. It may even be possible that this approach gives many results more easily and directly than the standard procedure.

What I have seen in the text of Claes Johnson is certainly not a complete and valid presentation in this line of thought, but it may be partially correct and it might be possible to continue in this direction and reach correct results. I have full trust that the final results would agree with the results of the standard approach, but it is likely that the same results would indeed be reached in a way that does not include back radiation. This would be an extension of the idea of wave-particle dualism. The description in terms of waves does not include back radiation, but it would still give the same quantitative results.

Agreeing with accepted physics does not require dogmatic adherence to the standard way of describing the details.

agreed, that’s what is a little bit disturbing about QD imho: not easy to draw where quantum description start, and where classical physics end. For example, a lot of classical QD imply wave/particles in external potential….but those potential are themselves caused by phyical objects, so by W/P assemblies. Why are they represented by perfectly know and unchanging potential fields them, like some kind of ghost of classical Newtonian entity? I guess QD has progressed since (I only have some training about early stage QD, probably from the Plank/Einstein era, and still it is vulgarisation).

But I have 2 problems with C. J. approach. one is that is is hopeless imho to try to use Maxwell equations only, you have to introduce some quantization, or an equivalent effect, to avoid molecules to radiate even at 0K just by electron orbiting. Or you can say that bohr atom model is not correct, but this is just another way to make QD come back through the backdoor…As you said, QD can be introduced in many ways (which I find slightly disturbing, but I also agree with you that QD is one of the most (if not the most) succesful physical theory), but Maxwell has to be complemented somehow. C.J approach seems to be “add a phenomenological structural damping for elementary resonators”. I am fine with that, even if I think it explain less than quanta as introduced by planks and so is a poorer approach.
The problem number 2, unfortunately, can not be bystepped just by saying that choosing the method is a matter of personal preference: the radiative exchange presented is not equivalent to S-B law, we have R = 4 s T³ (T-T_cold) versus R = s (T⁴-T_cold⁴).
Not the same, and I prefer S-B for symmetry reason (the fact that each body radiates without having to know his surrounding is a huge plus in S-B), but here personal preference has no play: the difference is so high as to be easily tested by simple calorimetric experiment.

Maybe I have misunderstood C.J., and his derivation is in fact strictly equivalent to S-B. But then, why the fuss? it is only a re-interpreation of the same formula, and by definition, should have exactly the same effect, being used for computing calorimeter calibration, heat exchange in a turbine, or GH effect…

kai,
I am not for CJ, I am only noticing that much that has been used against it is not valid argumentation but presents lack of knowledge about the variety of the ways the same basic physics can be approached in practice.

The full dynamic equations are very complex and cannot be solved directly. Therefore some ways have been developed for solving then stepwise. The standard approach goes through the micro physics. The method is based on perturbation theory which is equivalent to introducing photons. The method implies also discussing the emission and absorption of the photons by transitions between the ground state and vibrational state of individual molecules. Each photon is a separate entity having a random phase of EM fields in relation to other photons. This is in accordance with a state collapse in the Copenhagen interpretation of quantum mechanics. Thus we describe the wide macroscopic phenomena as a combination of a huge number of independent microphysical phenomena. This leads to good results because the higher order terms of the perturbative analysis are very small and the coherence between micro-processes very weak.

While the above approach has provided very good results, it is not the only possible approach of making the original insolvably difficult problem solvable. Another approach would be to look at the macroscopic problem and use some clever averaging and smoothing to make the field equations solvable. I am not at all sure that this can be done in practice, but it is not excluded. If the approach works in is likely to involve solving Maxwell’s equations with some clever way of describing the interaction of electromagnetic fields with molecules. This interaction must conform with quantum mechanical description of molecules, i.e. with the Schrödinger equation, but this may be done without the use of the state collapse of Copenhagen interpretation. Like the Schöringer’s cat the molecules will remain both alive and dead, i.e. it is not known whether they are in the exciter on in the ground state.

What I have written is highly speculative and would have its right surrounding in a site, where different interpretations of QM are discussed, such as Copenhagen interpretation, many worlds, hidden variables etc. What I have written is in line of my own longstanding thoughts on these issues and I do not know, how many others would agree on them.

One may ask, how is the above second approach consistent with the fact that we can measure backradiation with a measuring device. There is no problem in that. In that approach electromagnetic field is present everywhere in space and the measuring device is interacting with this field.

In this approach the field is no more forward or back radiation, it is just EM field in a state consistent with all matter that interacts with it. Gas that is conventionally described as radiating back-radiation is influencing this field reducing the energy carried by the field upwards, but there is not specific back-radiation.

Backradiation is unstable because it would correspond to a negative dissipative effect, which is unstable just like the backward heat equation with negative diffusion. This is well known and supported by solid math. You cannot unsmooth a diffused image by negative diffusion. If you don’t believe try it
in photoshop.

It is not: “back radiation” (I put it in quotes, because there is only radiation, not main or back) is always lower than the other one. You can not analyse stability of “back radiation” only, you have to include all radiative exchange in your stability analysis. Including all radiative exchange, S-B always predict net heat exchange from hot to cold, never the opposite. In a many-body case, it is thus a diffusive equation, not a negative diffusive equation, and it is thus stable. If you do not agree with this statement, you just have to provide an example using S-B relations that would lead to unstable situation, where entropy would decrease (hot will get hotter, cold colder). Best would be to start with isothermal and find a perturbation that grow, but even in non-isothermal situation, if you can find an example where entropy is decreased by S-B, it would be enough ;-)

There’s no ‘negative diffusion’ and no instability. The cooler body transfers heat to the warmer one, but the warmer one transfers more heat to the cooler one, so the net heat flux is always from the warmer to the cooler.

Consider a 1-D system of two black body plates set at 100K and 400K. The Stefan-Boltzmann flux is 1446 W/m^2. Next, insert two intermediate plates, positions otherwise irrelevant. The steady-state temperatures become (100K, 304.53K, 361.62K, 400K) and the flux drops to 482W/m^2. Next insert a central fifth plate. The temperatures are now (100K, 283.67K, 336.69K, 372.36K, 400K) and the flux 361 W/m^2. Adding the fifth plate has lowered the temperature of one plate and raised that of another.

Does Johnson’s physics yield these numbers? (I have no idea!) If not, there’s a simple experiment to do. If so, where’s the beef?

I have no doubt that he would since that is standard Radiational Heat Transfer Engineering which is applied in such situations every day! I invited Claes to apply his method to such problems several times but he ignores it. I guess the mathematician likes to derive his new equation but can’t test it against real world situations.

I think those are very good questions to ask in my opinion. I have always thought that the best way we can understand the effect of manmade CO2 was to calculate the extra time energy spends in the earth climate system in response to an increasing greenhouse effect. I think that way of thinking about the problem gives us the best handle on how big of an issue it really is.

I think the essential problem, however, is that the transient nature of climate is neglected in most of these treatments. As a molecular physicist who studies time-dependent transient behavior of absorbing molecules, it seems to me that this is the area in which climate science needs the most work.

I heard a talk by Ricky Rood in which he told an audience member that the typical atmospheric transient is gone in a few days, yet La Nina and El Nino events, which represent the coupling of the atmosphere and oceans, have very long time transients. These could be represented in the amplitude fluctuations of the El Nino/La Nina events, their phase or their damping and range from a few weeks to a few years, maybe even decades. We don’t even know yet. So his answer struck me as quite odd.

The steady state solution in most important cases in a limiting case. Since we (the community of scholars and interested public) are convinced this case is pretty well understood, it’s time to move on to transient scenarios that better model the real world each person sees on a year to year basis. I think from there we might be able to answer the questions you pose. I think they deserve an answer.

1. Time is an important component of computations involving radiative warming of the Earth and atmosphere as a function of the concentration of CO2 and other greenhouse gases. However, this is not because of the time needed for radiative energy transfer within the atmosphere, which is almost instantaneous. Rather, it is because heating of the surface is a time-related function of specific heat capacity, combined with elements of thermal conductivity, and in the oceans, turbulence and convective mixing. More below.

I don’t know where your figure of 0.017 W/m2 for solar heat uptake come from – can you provide a reference to the relevant data? However, I’m not sure the figure is very meaningful. Land warms (and cools) much faster than water, but 70 percent of the Earth’s surface is ocean, and most of the heat from the sun and from back radiation originating in the atmosphere is stored in the ocean. Because ocean heat capacity is so enormous, diurnal changes in radiation entering from above exert appreciable temperature effects only near the surface. Mixing of the upper layers quickly averages out these effects, so that temperature changes in the entire mixed layer are very unresponsive to short term variation in radiation. For this layer, one tends to think in terms of months and years, and for the entire ocean, centuries to millennia – not hours. In essence, most of the W/m^2 radiated into the ocean is absorbed, the remainder being reflected as a function of albedo, which in the case of water is relatively small. Of course, increased absorbed radiation is met with an increase in emitted radiation, along with an increase in latent heat transfer via evaporation and convection. I suspect the figure you cited, if accurate, may refer to very superficial layers of the ocean, but in any case, one must specify what “surface” is involved when citing such statistics. Ultimately, the warming from the exposure you describe will be greater than the figure you cite.

2. The number of molecules among which a photon’s energy is diffused is astronomical because of thermalization. The vast majority of excited CO2 molecules, for example, are de-excited by collision with neighboring gas molecules, thereby raising the average kinetic energy (i.e., the temperature) of their surroundings. Since the energy of each collision is immediately distributed widely via further collisions, one would have to calculate a mean number based on the Boltzmann distribution. I’m sure it could be done, but I’m not sure how informative it would be for our purposes.

3. By similar reasoning, I’m not sure how informative we would find an analysis of the mean time a photon’s energy spends in the climate system, although the calculation could probably be done. Perhaps it would provide a clue as to the warming potential of greenhouse gases, but if so, it would be a very indirect means to that end. In explaining the greenhouse effect to non-scientists, CO2, water, and other GHGs are sometimes described as “delaying” the escape of radiation to space, but the description is misleading. It is true that energy radiated from the surface, and absorbed and reradiated many times before escaping is delayed in a temporal sense, but the time delay, which is extremely small by our mundane concepts of time, is not the mechanism underlying the warming. Rather, warming occurs because of a temporary imbalance between the incoming solar radiation and the longwave radiation escaping to space due to the fact that the GHGs intercept upwelling radiation and cause it to be reradiated in all directions including downward. This imbalance is translated into increased radiative energy absorbed within each layer of atmosphere down to the surface, and a balance can be restored only when each of these entities warms sufficiently so that outgoing longwave radiation, which depends on temperature, returns to its former level. Because escape is impeded by higher GHG levels at any given altitude, energy must reach a higher altitude for adequate escape, and since higher altitudes are colder, they must be warmed from below to mediate IR emission sufficient for a full restoration of balance. In essence, the greenhouse effect can be quantified not by asking “how long?” but rather by “how high, and how cold?”, and computing the results over a spectrum of wavelengths. These theoretical calculations are now well confirmed by observational data.

4. I’m surprised by your claim that empirical evidence refutes a warming role for CO2. I’m familiar with the climate science literature, including data from recent and current measurements, as well as data extending back more than 400 million years – all converging from multiple sources to demonstrate a very substantial role for CO2. It would be illegitimate in science to insist that any phenomenon, including a warming role for CO2, can be demonstrated with 100 percent certainty, but in this case, the level of certainty is high enough to approach 100 percent. I’m unaware of any evidence at all that suggests the absence of CO2-mediated warming, and so I believe your statement is simply wrong. However, I would be interested in appropriate data references that have led you to make your claim. In truth, though, the realistic element of uncertainty is not whether CO2 warms the climate appreciably, but to what extent. This quantitation has been the subject of numerous discussions here and elsewhere.

‘…although the calculation could probably be done. Perhaps it would provide a clue as to the warming potential of greenhouse gases, but if so, it would be a very indirect means to that end.’

I think this statement is only meaningful if we assume the climate system is a strictly steady state system. Obviously, for a steady state system time dynamics are not interesting because we’ve assumed that they have dissipated, whatever they were. That is the definition of steady state.

The climate system, however, is inherently dynamical and its the transient in the climate system that cause the up ticks/down ticks in snowstorms, hurricanes, floods (when people aren’t causing them) and the other ‘wonderful’ events we witness in this world.

I also think that it is incomplete to think that the radiative transfer happens instantaneously. I agree that when we focus on the gases in the atmosphere thermalization occurs very quickly and when a lone CO2 or water is excited and along enough, radiative decay happens faster than we can perceive. That said, it may be possible for transients in the atmosphere to manifest themselves in other aspects of the climate system and get propagated for much longer times.

Couplings to the oceans, cryosphere and biosphere are very poorly understood at this point in time, especially because they are heterogeneous. I can imagine reasonable cases in which transients of greenhouse effect could cause plant growth that impacts an ecosystem for many years or cause the overturning of a current in a different way or melts/freezes portions of glacier, in all cases causing changes that last much longer than ‘instantaneous’.

To the zeroth order, I think the steady state picture provides a useful tool. I just wonder if we’ve used most to all of its utility.

Maxwell – I agree completely that in our current non-steady state, time constants are an important element in determining climate dynamics. I tried to make that point when I mentioned the very long times involved in ocean heat storage. I can’t agree with John that these elements are neglected, and in fact, both models and observational studies are often aimed at quantifying the time relationships. My more limited point was that radiative changes in the atmosphere in response to a change in radiative balance at the top of the atmosphere occur extremely rapidly. It is the non-radiative elements of climate dynamics, including convection in the atmosphere and energy transport and storage in land and oceans that consume more time.

I’ve been looking for easier ways to understand what’s happening to global temperature and why. The concepts of back radiation and the second law of thermodynamics both seem to me to make the reasoning very complicated, with the result that one can use these concepts to prove anything you want, including that the planet is cooling, or that it is warming. We’ve seen endless examples of this sort of reasoning not just on Climate Etc. but all over the web.

So I asked myself, is there one single phenomenon to which all such questions can be reduced, which doesn’t allow the outcome to be argued either way according to what one believes?

I think there is. It is how many photons are leaving Earth. Or how much radiation if you don’t like thinking about photons.

There seems to be no serious debate as to how much radiation is arriving. The intensity of sunlight at 1 Astronomical Unit (AU) from the Sun, which is where we are, is around 1370 W/m2. The area of the Earth capturing this as a disk is around 127 .5 million sq. km (precisely one quarter of the area of the surface of the Earth as a sphere). And Earth’s albedo is around 0.3, meaning only 70% of the intercepted insolation is heating Earth.

Multiplying these together gives 1.37 * 127 * 0.7 = 121.8 watts, with the decimal place 3+12 = 15 places to the right. This comes to 122 petawatts, a phrase that’s easily googled if you want to check the math.

For equilibrium, that is, in order to maintain a steady temperature, Earth must radiate 122 petawatts to outer space. Each photon of that radiation can come from only two places: the Earth’s surface, or a molecule of one of the greenhouse gases in the atmosphere.

These two sources of radiation behave very differently. Earth’s radiation is sufficiently broadband as to be reasonably modeled as radiation from a “black body” at around 288 K. In sharp contrast the greenhouse gases radiate at certain wavelengths called emission lines. These lines coincide in wavelength, if not always exactly in strength, with absorption lines.

The radiation leaving Earth can therefore be classified into two kinds: the black body radiation leaving the surface of the Earth, and the emission lines leaving the atmosphere.

The last line of these tables shows that 80% of the blackbody radiation leaving Earth’s surface is between 7.62 and 32.6 microns in wavelength. Some of these wavelengths are open to the escaping radiation while some are blocked by the absorption lines of the atmosphere’s many greenhouse gases.

The two dominant greenhouse gases are H2O or water vapor and CO2 or carbon dioxide, having respective molecular weights of 18 and 44. (There are variants of these with an extra neutron or two in each atom but those are in a distinct minority and hence can be ignored here.)

Human population has been growing exponentially for many thousands of years, doubling around every 90 years or so in the past couple of centuries. The per capita fuel consumption has also been growing exponentially over this period, with the result that we are doubling our contribution of CO2 to the atmosphere every three or four decades.

The late David Hofmann, shortly after his retirement as director of NOAA ESRL Boulder, claimed a more precise doubling period of 32.5 years, along with 1790 as the approximate date when the residue remaining in the atmosphere from our additions was 1 part per million by volume (ppmv) of CO2. He assumed this residue to be added to a natural base of 280 ppmv during the previous few centuries.

Barring any strenuous objections to these numbers I’m happy to go along with them. The upshot is that we can estimate CO2 over the past few centuries as 280 + 2^((y − 1790)/32.5) where y is the year. For example if y = 2010 then this formula give 389 ppmv which is in excellent agreement with the CO2 level measured at Mauna Loa.

All this arithmetic is mainly to make the point that we are increasing the CO2 in the atmosphere, while adding a little corroborative detail.

Of the photons escaping from Earth’s surface, some are at wavelengths blocked more or less strongly by CO2. Call a wavelength closed when the probability that a photon leaving Earth’s surface will be absorbed by a CO2 molecule before reaching outer space is less than 1/2, and open otherwise. (Sometimes 1/e instead of 1/2 is used, in conjunction with the terminology of unit optical thickness, but it doesn’t make much difference to the outcome and 1/2 is easier to relate to.)

The HITRAN08 database of CO2 absorption lines lists 27995 lines in the above-mentioned range from 7.62 microns to 32.6 microns. Currently 605 of those lines are closed. According to Hofmann’s formula CO2 will double by 2080, which will close a further 120 lines. This will leave 27,270 absorption lines of CO2 still open, of which only a further 2502 lines will close when and if the CO2 level rises to 40% of the atmosphere by volume, a more than lethal level for all mammals.

Now the closed lines aren’t truly closed because they can emit as well as absorb. These account for the photons radiated to space from the atmosphere, as opposed to from the surface of the Earth.

It is tempting to argue that increasing CO2 will increase the radiation from these closed lines. To see why this is wrong, picture the CO2 molecules in the atmosphere as grains of white sand on a black sheet of cardboard. When there are very few grains the cardboard looks black, but as the grains fill up it gradually turns white. Furthermore the more grains there are, the higher above the cardboard are the visible grains.

The same effect is happening with CO2 molecules that both absorb and emit. For any given wavelength, with very little CO2 an observer in outer space looking at just that wavelength sees the surface of the Earth. As the CO2 level increases the observer starts to see CO2 molecules covering the Earth’s surface. And as the level continues to increase, the visible CO2 molecules are found higher and higher, just as with the grains of sand. But the higher they are, the colder, at least up to the tropopause (the boundary between the troposphere and the stratosphere). So radiation from CO2 molecules decreases with increasing level of CO2 in the atmosphere. This is not true of the CO2 molecules in the stratosphere, but there are too few of them to make a significant difference.

This is a complete analysis of the impact of increasing CO2 on how much radiation leaves the Earth at each wavelength. It describes what’s going on both simply and precisely, unlike accounts based on back radiation and other phenomena which are far harder to analyze accurately.

This analysis ignores the impact of feedbacks, most notably the increase in water vapor in the atmosphere expected from the temperature increase induced by the increasing CO2. That increase could work either way: more water vapor could block heat at other absorption lines since water vapor is a greenhouse gas. But water vapor also conducts heat from the surface to the clouds, a cooling effect. Hence the net effect of such feedbacks needs to be analyzed carefully.

However the feedback cannot result in an overall cooling, since the feedback depends on CO2 raising the temperature in order to evaporate more water. The question is only whether the feedback reduces the warming effect of CO2 by some factor between 0 and 1, a negative feedback, or enhances it by a factor greater than 1, a positive feedback. It cannot reduce the warming effect to zero since then there could be no feedback.

John, you raise an excellent question, one that was asked in the 19th century. Based on the thermal insulating qualities of the Earth’s mantle and crust, Lord Kelvin calculated that the heat at the core must be leaking out at a rate that would prove that Earth could not have formed more than 50 million years ago.

However the geologists were unable to reconcile Kelvin’s figure with what they were observing in the geological record, which suggested the Earth was billions of years old. This huge discrepancy was a great puzzle for a while, until it occurred to physicist Ernest Rutherford to calculate the heat that could be generated by a small quantity of radioactive material (uranium etc.) in Earth’s crust. He found that it would not take much to exactly balance the amount of heat leaking out through the crust. If this were not so, in the four billion years of Earth’s life the core would long ago have cooled down to something closer to the surface temperature. In effect the small amount of radioactivity in the crust is acting like a stove to keep Earth’s core at a steady temperature over billions of years.

Global warming has only kicked in strongly over the past half century. Compared to the billions of years in which the core could have cooled down but didn’t, half a century is nothing timewise.

You say:This analysis ignores the impact of feedbacks, most notably the increase in water vapor in the atmosphere expected from the temperature increase induced by the increasing CO2. That increase could work either way: more water vapor could block heat at other absorption lines since water vapor is a greenhouse gas. But water vapor also conducts heat from the surface to the clouds, a cooling effect. Hence the net effect of such feedbacks needs to be analyzed carefully.
I have led myself to make the calculations, from the observational and experimental derived formulas, and have found the results corresponding to Photons Mean Free path and to Photons Lapse Time before the absorbent molecules of the atmosphere hit or diffuse them. I have done it for each component of the atmosphere and for the whole atmosphere. Most relevant results are as follows:

Those are well reviewed results, supported by observation and experimentation.

Now tell me, do you think the “downwelling” radiation heats up the surface? Why to talk about a “downwelling” radiation when we perfectly know that the possibility for the energy to be emitted is, equally, at every trajectory?
Besides, there is a photon stream, stronger than any photon stream coming from the atmosphere that nullifies any backradiation” or “downwelling radiation from the atmosphere. The term “backradiation” is absolutely invented and incorrect; why? Because the air is not a mirror.
Why dismissing convection, when we perfectly know that it is the prevailing way of heat transfer in the atmosphere?

The term “backradiation” is absolutely invented and incorrect; why? Because the air is not a mirror.

Since both you and I have rejected the concept of “back radiation” as not helpful (if not for exactly the same reasons—in particular I don’t consider it incorrect, just harder to work with) it sounds like we’re both more or less on the same page regarding that aspect.

Why dismissing convection, when we perfectly know that it is the prevailing way of heat transfer in the atmosphere?

I agree that convection can make a difference in the thermal insulating qualities of the atmosphere, for example by transporting heat from the surface upwards, e.g. via thermals. What I was focusing on however was the heat leaving Earth for outer space, which cannot be accomplished by convection because there is no significant flow of matter from Earth to outer space. Radiation is the only way available to Earth to shed the 122 petawatts of heat that the Earth is constantly absorbing from the Sun. Hence to understand how an increase in CO2 could heat up the Earth it suffices to consider how increasing CO2 blocks some of the departing radiation.

One point I neglected to make is that the heating resulting from blocking radiation raises the temperature of the Earth until it is once again shedding 122 petawatts, the amount of heat it is absorbing from the Sun. The additional lines closed by increasing CO2 make for a smaller atmospheric window through which to push those 122 petawatts. In order to get the same amount of heat through this smaller window, Earth’s temperature has to increase. This is analogous to having to raise the voltage across an increasing resistance if you want to maintain a constant current.

The misconception of science is that it is suppose to be a balanced system.
It is far from it.
Our concept is so far out of balance with what is actually happening due to the past down theories that apply to ALL of the planet at the same time.
Hmmm. Round Planet rotating.

Claes, the issue is this. For the past many decades climate researchers and physicists have put their equations, data and analyses out there. The story of IR emission by gases hangs together very well in terms of observations, theory, and radiative transfer modeling. The challenge is in your court to demonstrate that any of this is incorrect, and to put forward a coherent case that convinces people that are knowledgeable of the observations, theory, and modelling. IMO you have failed to do this. This isn’t about exchanging equations. The body of physics and chemistry that underlies the calculations of gaseous absorption and emission made by line-by-line radiative transfer models is well understood, apart from some issues related to the water vapor continuum absorption under very high humidity conditions (this is understood in terms of the observations, but not theoretically, and hence is parameterized empirically in the models).

Judy: You just repeat a mantra without mathematical basis. I prove that the “backradiation” of the KT energy budget which you say you believe describes real physics, is not to be found in Maxwell’s equations, which have shown to model almost all of macroscopic electromagnetics. You say nothing about this proof. You are still convinced and probably teach your students that in some mysterious way a cold body sends out some mysterious particles which in some mysterious way heats a warmer body. It is a mystery in every step from scientific point of view, but mystery is not science. I have demonstrated that “backradiation” is fiction, and it
is now up to you show that my proof or assumption is incorrect, or accept it as correct. Can we agree on this? So what is wrong with my argument?
Have you read it?

Your argument is incapable of explaining radiational heat transfer which is used in practical situations everyday where theoretical predictions are confirmed by measurement. You have dodged the challenge to apply your ‘theory’ to a practical situation, until you do you’re just hand waving. Show your working for us to follow your calculations, until you do it’s just ‘hot air’, I’ll await your calculations.

Do you dispute that if you put an infrared radiometer on the surface of the earth and point it upwards, that it will measure an IR radiance or irradiance (depending on how the instrument is configured)? Go to http://www.arm.gov for decades worth of such measurements. And that this infrared radiation comes from IR emission by gases such as CO2 and H2O and also clouds? If you say yes, well this is what people are calling back radiation (a term that I don’t use myself). If you say no, then I will call you a crank – all your manipulations of Maxwell’s equation will not make this downwelling IR flux from the atmosphere go away.

even though “back-radiation” can be measured by a thermocouple or thermister that has been cooled by liquid nitrogen to temps lower than the atmosphere in order to measure said “back-radiation.” [alternatively, less expensive units can measure “back-radiation” at ground temperature by e.g. a thermister increasing or decreasing resistance (depending on the type) due to the thermister losing heat to the atmosphere and a mathematical correction is applied to measure temps lower than the sensor]

Given the amount of information you have provided for your ‘quiz’, it is not possible to tell which body is warmer. Two bodies at different temperatures can both emit photons at both 9 and 10 um. The distribution of frequencies emitted is very large.

If you are more precise and specific with the question, I should be able to answer it.

More to your point though. If one blackbody gives off energy, and another gives off energy, why wouldn’t they flow energy to each other?

Johnson is basically saying that one blackbody (the warmer one) KNOWS that the other blackbody is colder. And he is saying with by only referring to this fact via the source-less Maxwell’s equations, according to his comments here.

you do realize that Einstein was the first to propose the existence of the photon, don’t you?

In 1678 Huygens proposed that light was a wave, contradicted in 1704 by Newton who claimed light consisted of particles. Newton’s particle theory was generally accepted over Huygens’ wave theory until 1801 when Young’s two-slit experiment showed that Huygens was right. The wave account then survived for a century until Einstein showed that Newton was right too.

However Huygens had no idea what the wavelength was, while Newton had no idea how big the particles were or how a mirror could reflect them. So neither of them had as much claim to their respective theories of light as Young and Einstein, who were the first to actually observe respectively the wave and particle forms of light.

Newton called the particles “corpuscles” while Einstein called them “light quanta.” The snappy term “photon” was introduced later.

Yes, but what it can do however is reduce the loss of heat. When (for each square meter of surface) you have U watts of heat going up and D watts going down, with D < U, the net loss of heat from the surface is U − D.

If U is 396 W and D is 0 W then the net loss of heat from the surface is 396 W. If however D is 333 W then the net loss of heat is only 63 W. This does not contradict the 2nd law of thermodynamics because the net flow of heat is still from the hotter to the colder entity, there just isn't as much flow between two entities that are at relatively similar temperatures. Although 63 W might seem like a lot of heat, in terms of temperature the difference is only 289 − 277 = 12 degrees. (100*sqrt(sqrt(396/5.67)) = 289 K.)

There is incidentally a fundamental error in Dr. Anderson’s website. He says “Each time a greenhouse gas molecule absorbs ground radiation energy, it sends half of it back to the surface.” While it’s true that half the energy goes up (not necessarily straight up) and half goes down, the latter need not reach the surface because it may be intercepted by another GHG molecule first. That possibility is one of the things that makes it extremely hard to calculate just how much heat GHGs intercept.

This is why I recommend my much simpler way of calculating it, namely solely in terms of the number of photons escaping to outer space. Those are the only ones capable of cooling Earth: if none escape the temperature will rise enormously. Those photons reradiated from the atmosphere bounce around the atmosphere, sometimes hitting the ground and sometimes escaping to space, and are much harder to reason about. Rather than even try to reason about them, just ignore them altogether on the ground that only those photons that escape to space make any difference to global temperature.

a couple of nit picks. Some of the IR goes sideways and depending on height some of the generally downward doesn’t even go to earth as the earth is round and not infinite, so, less than half goes in the direction of the ground.
Increasingly less with altitude.

As far as what is moving between earth and GHG’s, part of the argument is whether observed IR really transfers a quantum of energy that translates to heat.

Various arguments include the fact that a photon is a wave front until it actually transfers its energy to something, which means in quantum mechanics it simply may not do it where we think it should.

As there really do appear to be teleconnections between “particles” the photon may KNOW not to transfer its energy to the higher temperature bit just like in conduction where the material KNOWS not to move energy from cold to hot.

Finally, fitting in with the idea of a slower cooling of the surface, the warmer surface may simply reradiate the energy from the incoming IR without it affecting the temperature.

Then there is the older solid science of wave interference. Long before quantum theory was relatively solid it was known that waves interfered and cancelled each other. Why that is not considered as a possibility for colder not heating warmer or not slowing the warming I simply don’t understand. The energy equations show a NET energy flow and the interference, scattering, and cancellation could be components of creating this NET flow. In the case of a NET flow it should be noted that there would be NO slowing of the rate of radiation from the hotter surface unless the scenario where the photon coming from the colder source is absorbed and reradiated is correct. I am unsure why the lower energy photon would be able to cause a quantum increase in the warmer material though. Again, where are the quantum mechanics to explain this stuff!!

My problem with the reradiation of the colder sourced IR is that there is an additive effect that would seem to cause more warming or at least extending the cooling time. This should be measurable. If it isn’t the effect probably isn’t large enough to worry about. The problem with the current numbers is that they do not appear to break out the effects of conduction from depth in the surface. This is a small effect, but, so is the amount of CO2 heating that is alledged to cause feedback with water vapor.

So many choices and so few people with the skills to guide us to the correct conceptualization of what is actually happening.

Kuhnkat,
The quantum electrodynamics (QED) developed by Feynman and others is an extremely successful theory in describing how photons are created and how they interact. It has been tested empirically to a better accuracy than perhaps any other physical theory. From QED we know how photons interact with material. We know that the photons do indeed release their energy in well understood ways. The is no change that the alternatives that you propose might be true.

Yes. And I am almost sure you can check that low frequency photons can heat “high” temperatures bodies, if, like most westerners, you have a microwave.

The food you put in is usually between 270 and 300 K. It is very rapidly heated to 370+K by photons at 2.4 GHz, about 0.1 m wavelength. I do not have blackbody emission curve at hand, but this should be the typical max emission wavelength for a bb opf a few K, maybe 10 K max, no? Much lower than the food temp, for sure. So why is it heated? Because magnetron is a coherent source? I doubt it, nowhere in the heating proces is coherence required afaik…

It is very efficient. Do you think microwave would have been introduced for industrial food heating if they were not? (the first one were much more powerful than the current one – they were scary ;-) ).

Efficiency for a heating apparatus is something extremely easy to achieve though, depending on how you measure it.
typically almost 100% of input energy is converted to heat…because everythin is ultimately converted to heat!
So I guess you refer to heat energy IN FOOD/input energy instead total heat energy/ energy input (which is usually near 100% -possibly escaping sound and EM wave are absorbed too far to be counted).

For the “food” efficiency, microwave ovens are very efficient. Magnetron are nice efficient device (I am quite fascinated with tube-age power electronics, klystron, fusor, all that stuff. Nice that everybody have his own magnetron nowadays) , and not much heat is lost outside the oven nor transmitted to recipient (well, it depend in what you put your food). Or maybe you refer to efficiency compared to a perfect carnot cycle (hence you heat pump reference). Sorry, I do not know of any food warming technology using heat pump. Maybe there is, but I never saw any. If there is, I guess for large amount of food it can me more efficient than microwave…
Why, you are just about bringing to market an ultra-efficient combined fridge/oven based on heat pump? Congrat to you, but what does it have to do with C.J. theory about radiative heat transfer???

it is interesting you couch your closing sentence to me with the phrase “there is no chance” when theoretical physicists tell us that the universe may just be one of those chances that you blithely suggest doesn’t exist.

Quantum mechanics, as I am sure you are much more aware than I am, is based on statistics. Statistics allow for many stranger things than my simpleton maunderings.

But, I am a hardheaded simpleton. Can you refer me to experiments showing the increased radiation from a heated object caused by moving a cooler object close to it??

You could probably do an experiment yourself at home that would test the ability of a cooler object to raise the temperature of a warmer object. It wouldn’t be perfect, but should give a reasonable approximation.

Start with a cool room, and in the center, a 100 Watt light bulb. Turn on the bulb, and let the room temperature equilibrate. Also place a thermometer against the light bulb (shielded from outside influences) and record the temperature at the surface of the bulb. At this point, the bulb is radiating 100 W and the room is losing 100 W through walls, windows, etc.

Now surround the bulb at a distance of about 1 meter with wire mesh at room temperature. The purpose of using mesh is to provide space for air currents to escape so as not to interfere with convection. We can also leave the mesh open at the top so that rising heated air will not affect it. Also, because the conductivity of air is very low, we can reasonably assume that most heat transfer will occur by radiation – admittedly, it would be better to perform the experiment in a vacuum, but that wouldn’t be practical.

Place a thermometer on the mesh (again shielded, so that it records only mesh temperature). Allow equilibration. The room temperature will not change, because 100 W are still flowing into the room – the amount from the warmed mesh compensating for the reduction due to heat absorption by the mesh.

Here are my questions:
1. Do you agree that the mesh will warm due to radiation absorbed from the light bulb?
2. Do you agree that the mesh will remain cooler than the light bulb surface, because not all the 100 W are absorbed by the mesh?
3. Do you agree that the warmed mesh will radiate some of the wattage it receives back to the light bulb?
4. Do you agree that the surface of the light bulb will also continue to receive 100 W from its internal heating element?
5. Do you agree that the internally generated 100 W plus the W from the mesh will exceed the wattage the light bulb surface was receiving prior to being surrounded by the mesh?
6. Do you agree that at equilibrium, the light bulb surface will now be radiating the W described in 5?
7. What do you think will happen to the temperature of the light bulb surface? Why?

Kuhnkat – I’m not planning to do the experiment, because I don’t feel a need to prove anything. However, I would still welcome your thoughts about how it would come out on the basis of the questions I asked. I also wrote those with the thought that other interested readers besides yourself might appreciate the reasoning that has been expressed by many of us regarding the ability of a cooler object to raise the temperature of a warmer one, as long as the cooler object didn’t depend on its own energy but could gain energy that originated from an external source.

If you would like to answer the questions simply from the perspective of a thought experiment, I hope you’ll go ahead.

As some of my writing in this chain may appear obscure and even support Claes Johnson’s texts, I want make clear that I do not see anything wrong with the standard description involving photons, back radiation and transitions between ground state and the vibrational state of CO2 molecules. I wanted only to tell that the same physics with the same conclusions may perhaps be formulated totally differently. This alternative formulation would be closer to, what Claes Johnson has presented, but would definitively not change the results of the standard approach, which rest on solid experimental and theoretical knowledge of physics. Thus I disagree totally with all his statements that would modify the final conclusions.

Claes,
The physics is the same, but it can be described in different ways. The only way that si well developed and known to work includes back radiation. It may be possible to drop the particles and stick to fields without (second) quantization, but nobody has developed theory on that basis.

The wave-particle duality is reality when ways are searched for describing quantum physics in classical terms. People cannot discuss directly in quantum physics. Therefore such different classical type descriptions are used although there is just one real quantum physics behind.

Back radiation is a part of the particle type description. It would not be part of the wave type description if that would really exist. The physics would still be the same. Using Maxwell’s equations is a small step in this direction, but it has not been made complete (by you or anybody else as far as I know).

To your claim 1) aka non existence of “back radiation”.
As you prefer equations , so just a few very simple ones.
Let us consider 3 interacting systems.
S1 is the void
S2 is the atmosphere
S3 is the Earth
We will consider that we know some things about the Earth and the void but the atmosphere is complicated . There are clouds , moving gases , many mysterious and complex processes.
So we will consider S2 as a black box where the only knowable parameters are the energy fluxes at the interfaces.

The only assumption we will take is that S2 (atmosphere) and S3 (Earth) are in a steady state . They may transport and transform energy internally as they want but they neither store it nor release it.
For S1 (Void) we will assume that it is in an approximate radiative equilibrium with S2+S3.
If we call the energy fluxes F (W/m²) then we have the following equations :
At the interface S1-S2 we have F1->2 = F2->1
At the interface S2-S3 we have F2->3 = F3->2
There is no contact and no interface between S1 and S3.

That is 2 equation , 4 unknowns.
However we can measure F1->2 and F2->1 and find that they are 340 W/m² and indeed approximately equal.

Remark : Of course the conservation of energy would require that I write the equation for the whole system and use energy (units J) for a certain time scale .
However once I have the TOTAL in and out energy , without loss of generality I can always divide the result by the surface of the interface and by the time to get back to fluxes (W/m²) which are more familiar . This of course doesn’t mean that it is assumed that the real fluxes are 340 W/m² everywhere . They aren’t . This “average” value is just what represents the energy conservation.

Back to S3 (Earth) . It is behaving like a grey body with an excellent approximation and emits according to F = ε.σ.T⁴.
When we integrate that over the whole surface and divide by the surface to get homogeneous units for all fluxes , we get a value of about 390 W/m² .
But the radiation is not the only component of the F3->2 flux .
We have also convection , conduction and latent heat transfers .
These 3 components can be computed and estimated to about 100 W/m².

Now only 1 unknown is left , the energy flux from the atmosphere to the Earth , and it is necessarily 390 + 100 = 490 W/m² .
What can that be ?
Even if the radiation from S1 (Sun/Void) goes completely through the atmosphere and we know it doesn’t, it is only 340 W/m².
There would be still 150 W/m² missing.
Convection and conduction towards the Earth is very weak because it is generally warmer than the atmosphere . Part of the latent heat may possibly return.
But whatever part of the 100 W/m² come back to Earth , it is still not enough .
As what is missing is neither convection/conduction nor latent heat it can only be radiation.

Conclusion : the atmosphere radiates “back” on the Earth (hence “backradiation”) at minimum 50 W/m² but actually probably significantly more because not all incoming 340 W/m² get through and not all 100 W/m² of convection/latent return to the Earth .

Thus it appears clearly that one doesn’t need any quantum mechanics , second thermodynamics principles or complex radiative transfers to conclude that the “back radiation” is a necessary consequence of the dynamics of the interacting systems S1,S2,S3 , as long as they conserve energy and are in a steady state at least approximately in a temporally averaged sense what we indeed observe.

Of course one can then become much more specific and explain how the “backradiation” can be deduced from the first principles too . But I won’t repeat what has already been written 100 times above , I wanted merely to prove its existence which can be of course confirmed either directly or by measuring the fluxes I defined above .

To your 2)
I largely agree with this opinion . I have exposed on other threads the arguments why I believe that. It has mostly to do with the fact that the system is governed by non linear dynamics which lead to spatio-temporal chaotic solutions.
Analytical or statistical considerations of spatial averages alone destroy all spatial correlations and have no possibility to recover the right dynamics.
As for the computer models, their resolution doesn’t allow and will never allow to really solve the dynamical equations.
What the computers produce are plausible states (e.g states respecting more or less the conservation laws) of the system but they are unable to discriminate between dynamically allowed and forbidden states.
This inability to discriminate between allowed and forbidden states becomes of course worse when the time scales get bigger .

But you are dismissing something very important, the total emittancy of the carbon dioxide, which, from experimentation and observation, is quite low. Well applied, the algoritms give 0.02 for CO2 and 0.01 for the whole mixture of the air, including water vapor. I must say that the algorithms derived from experiments give a ridiculous total emittancy for CO2, which is 0.002, at its current partial pressure in the atmosphere. Those are important parameters that are not taken into account by the current models. Carbon dioxide is not a blackbody, according to the most elemental definition of blackbody, but a graybody. The ignorance on this physics issuesintentonally or not, has taken to many people believe in backradiations heating up, or keeping heat, the surface.

Nasif I make no assumption about the blackbox atmosphere , what it contains and what it does .
I just observe and measure the fluxes at interfaces and apply energy conservation for systems in a steady state .
From there follows necessarily the existence of a radiation flux from the atmosphere to the Earth .
I do not attempt to say how much or by what mechanism because others have developped it ad nauseum .
I demonstrate that observation tells us that the number is strictly positive what is enough to establish its existence .

One area that Claes approach may give a new way of looking at a problem that has often been discussed on SoDs site.

That is what is the fate of the radiation from the colder object when it arrives at the hotter object.

To keep things simple lets say both objects are blackbodies.

Three tenable approaches are generally given.

1. No radiation from the colder object arrives.
2. The radiation arrives but is simply subtracted from the greater amount of radiation of every wavelength leaving the hotter object.
3. The radiation arrives and is completely absorbed.

Lets see how the 3 approaches deal with a simplified problem.
Let the colder body be at 290K

Lets consider an area of 1m2 some way from the colder object.
With the hotter object absent;
this area has a flux of 100W/m2 passing through it. (This means 100joules per second pass through the area)
If examined the spectrum of the radiation would be BB centred around 15um.

Now bring the hotter (1000K) object to this area.

Approach 1 says the radiation from the colder object no longer arrives at this area.
I consider this to be unphysical and will now drop this as it seems unreasonable.

Approach 2 says the subtraction of the radiation will still leave more radiation of every wavelength leaving the hotter object.
This satisfies the Stephan Boltzmann equation and also means that the colder radiation has no effect on the temperature of the hotter object.

Approach 3 says the 100Joules per second is totally absorbed and add to energy of hotter object.
The temperature of the hotter object is increased even if only slightly.
Effectively this means that 100J/s centred around 15um is transformed into 100J/s centred around 4.3um.

I would say this improvement in the “quality” of the radiative energy is forbidden by the second law of thermodynamics.

Further although approach 3 seems to satisfy the Stephan Boltzmann equation there may be a conflict there if the temperature of the hotter object increases significantly.

As you said: this point has been discussed dozens of times on SoDs site.
And your error is always the same: approach 3 is not “forbidden by the 2d law”. Approach 2 is impossible: it would suppose that the hotter object magically “knows” that the radiation comes from a colder object.
The approach 3 is the correct one.

Effectively this means that 100J/s centred around 15um is transformed into 100J/s centred around 4.3um.
I would say this improvement in the “quality” of the radiative energy is forbidden by the second law of thermodynamics.

Only if the same number of photons of higher energy were emitted, however this does not happen fewer photons would be emitted to balance the additional incoming flux.
An example in my lab I used a Nd:YAG laser which emitted at 1066nm which I then passed through a crystal which doubled the frequency to give me 533nm output. Two 1066 quanta are combined by the crystal lattice which then emitted a single photon at 533, no thermodynamic laws broken.

Phil. Felton
So you are saying that 100J of radiative energy at say 15um is thermodynamically equivalent to 100J of radiative energy at 4.7um?

….”Yes 100J is 100J, just fewer photons in the 4.7μm band.”…..

Now you must feel that this is on shaky ground.

With other physical equivalents of the “crystal” you could input low quality radiation say from seawater290K(radiative equivalent 15um) and by suitable “crystals” transform it in stages into 4.7um radiation equivalent to 1000K with no losses when absorbed.
With such a device ships would have no need of fuel simply extract it from seawater.
I think this is a clear violation of the second law
I think method 2 is correct

Oops! You’ve touched entropy. Does the entropy of a crystal diminishes or it increases? Does the entropy of that crystal surrounding increases or it decreases? Does the entropy of other crystals behave homogenously?
Would that crystal preserve its structure as long as the universe exists? You’ve got a biiig problem, and you did it alone.

Phil. Felton
The point you bring up is very interesting.
If a crystal can double the frequency of radiation with no energy loss then I will have to revise my understanding of the second law.
I have been to several websites to get more background information.
I have so far been unsuccessful.
The more relevant ones seem to be behind pay walls.
If you could provide a link to the thermodynamics of frequency doubling crystals it would be a great help

Are these crystals in a passive system similar to a crystal used to display a spectrum? My thought is that if it is in a powered system there may be a pump effect whereas a passive system would have much less possibility for a pump effect to be happening.

Why would anyone consider that combining two photons of one frequency into one photon of another frequency with no change in net energy be a plus or minus to either side of the argument? It would apparently conserve mass and energy and the frequency change is proportional?

As far as I know these crystals are only used in lasers.
The total power output will be less than the input.
So it might be using work to achieve what would not happen spontaneously a bit like a refrigerator.
However if someone can prove that a crystal can without any loses double the frequency of radiation then I will need a rethink on the second law.

Phil. Felton
It seems the radiation has to be of very high intensity like a laser.
Later on they talk about increasing the efficiency.
They dont specify whether this is energy efficiency however.
I will need to keep looking.http://en.wikipedia.org/wiki/Sum_frequency_generation

You are safe. The picture with the article shows a residual wave in addition to the desired second harmonic. It looks like only part of the beam is doubled and they filter out the residual for the microscopy.

kuhnkat
Yes it looks like the a fraction of the fundamental went through and the desired output the second harmonic is then utilised.
Its strange that to make sense of this phenomena we have to use the language of wave physics.
Why should a particle phenomena like the photon have harmonics?
It lends support to Claes ideas.
I would like to see a further analysis of the thermodynamics of this system.

actually I do not see it as strange at all. If there weren’t serious issues with the whole wave versus particle bit it would not have taken so many great minds so long to come up with the current compromises. The fact they settled on quantum theory as the explanation in no way invalidates the experimental data on what appeared to be waves at work.

I think there is an issue with people thinking of a physical particle when quantum theory doesn’t really say there are physical particles. My limited reading seemed to indicate that electrons moved closer to waves than waves moved to electrons. They are both just convenient ways for us to think about a sets properties and how they interact.

One of the ways Climate Scientists obfuscate the physics is confusing energy and temperature. They are separate at the level that is being discussed in climate science.

Getting a particular frequency out of a CO2 molecule does not mean it is the temperature as assumed by planck radiation. The frequency is determind by the molecular bond and not black body emission. The temperature would be indicated by the number of photons emitted by the CO2 molecule at atmospheric temperatures. Apparently CO2 has do be at combustion chamber temps for planck radiation to become significant.

In the cases I am aware of, the crystal which will take two photons and add them to create one photon of twice the energy, are very carefully selected or designed materials for having that effect on a particular wavelength photon. They do not do this for other frequencies of radiation incident upon them. So, the case you describe is a very special case and, yes, no violation of physics occurs in that case. But water, rock, and dirt do not generally have this property.

huh? It sure does obey inverse square law, if not energy conservation would be violated. Simply, it has very high directivity, the divergence angle of a typical laser beam is very low (often almost as low as his frequency allow). But within this very small solid angle, it sure obey inverse square law: in a perfectly transparent medium, the intensity of the laser will be much lower (and the surface illuminated much larger) 1 light year away, an even a few km away, the broadening is already noticeable…

The important distinction with respect to nonlinear optics is that the nonlinear optical process necessitates coherence in space and time between the mixing beams. From there one can get sum and difference frequency and harmonic generation. That’s why lasers are used in such situations.

But those are not the only kinds of nonlinear effects possible in a material. There are many more incoherent nonlinear processes in which the different photons acting upon a material are not coherent. Excited state absorption and spontaneous light scattering are two such situations which have fairly high cross-sections.

So while many rocks do not have the property of being crystals with specific bi-refringent properties, there are still many nonlinear optical processes that can occur, all which you neglect in the piece that has been featured in the comments here.

“…If the Earth’s surface is at a certain temperature, then it too will have a black body-like emission spectrum. Now suppose that CO2 absorbs a particular wavelength of infrared radiation out of that spectrum and then re-emits that energy at that wavelength back to the Earth’s surface. Can that photon absorbed by the surface raise the temperature of the surface? No. The reason it cannot raise the temperature of the surface is because to do so, the radiative spectrum has to move to the left in the diagram above. The shorter wavelengths on the left correspond to higher frequencies and to higher energies. For the surface to become warmer due to the absorption of the photon from a greenhouse gas, higher energy vibrational states must become occupied in the Earth’s surface materials. A photon from a lower temperature emitter cannot warm the surface to a higher temperature because that lower energy photon cannot excite the necessary higher energy vibrational modes. That photon can slow down the cooling of surface at night, since its emission at night will cool the surface and the returned photon will be at a higher energy than the surface is by the time the photon returns. This is the equivalent of the process when we put hot coffee in a thermos, thereby slowing down its cooling rate. But, the returning photons from the reflective wall in the thermos never heat the coffee to a higher temperature than it was at when it was poured into the thermos.

Whether a photon is absorbed by a material or not is dependent upon the electronic and vibrational states in the material which can be excited and the energy of the photon. The fact that a photon is incident upon a material does not mean it will be absorbed. The greenhouse gas theorists recognize this when the material is nitrogen or oxygen molecules, but they assume the Earth’s surface can absorb whatever strikes it, at least if it is a low energy or longwave infrared photon. But, just as visible light passes through window glass without absorption, this is not necessarily the case. The light photon is not absorbed in glass because glass has a wide energy band gap in which there are no occupied or unoccupied electronic states. Still higher energy ultraviolet energy may excite available unoccupied electronic states, which in turn will de-excite in time. Until they do, they can warm the glass. But visible light just passes through. The same is the case with some of the low energy, longwave infrared radiation returned from greenhouse gas molecule de-excitations. The Earth’s surface will not accept them since the excitable vibrational states are already excited and vibrating assuming that its temperature has not dropped since the returned photon was emitted by the ground. There simply is no available energy state able to accept it.”

Yeah but he’s made a few mistakes. Following his argument, by emitting photons the surface necessarily cooled the instant those photons left leaving energy states ready to absorb any returning photons.

In the equilibrium case of solar radiation flux upon the surface, the Earth’s surface temperature is constant and the emission of a photon does not cool the surface. Of course at night, with no incident solar radiation, the surface is constantly cooling as infrared photons are emitted. In that case, a photon absorbed by a water molecule or CO2 may result in emission of a photon from that molecule and the photon may be absorbed by the cooling Earth’s surface, thereby retarding the cooling. Where I said the emission of the photon from the Earth’s surface cooled it, I was talking specifically about the phenomena of cooling at night. I wanted to make sure the reader knew that I was not denying that the presence of infra-red absorbing molecules in our atmosphere can contribute to a retardation of surface cooling at night and to make it clear how it did this, when it could not do it in the case of the surface at a constant or increasing temperature.

Your support is clumsy: don’t you care that this theory is in contradiction with what Bryan said?
His theory and Bryans “approach 2” cannot be correct at the same time. Choose one side.
(anyway, they are both wrong)

Of course, here are the conceptual differences:
Brian: no backradiation (supposedly because the 2d law) with a theorical case of two blackbodies (so, total absorptivity).
Charles Anderson: backradiation, but absorptivity of the Earth surface = 0 for the longwave radiations (all the confuse 2d paragraph). That’s obviously false: you can check any textbooks for the absorptivity vs. wavelength for all the different type of opaque materials.

Ort: no, Bryan’s approach 1 is “no backradiation,” which he dismisses. Approach 2 is that there is “backradiation,” but the colder objects “backradiation” cannot heat the hotter object. This is exactly what materials physicist Charles Anderson explains in detail, and you fail to understand why the absorptivity is effectively 0 by a hotter temperature/frequency/entropy body from a colder body – did you even bother to go to his blog post instead of just reading the small excerpt?

The explanation is false. A black body goes never to a state where it would not absorb all radiation reaching it. The absorption leads unavoidably to the transfer of the energy of the absorbed radiation to the heat content of the body. The body is also radiating at the same wavelength, but the rate of radiation is not changed by the absorption. Thus the incoming radiation influences the heat balance of the body.

The same applies very closely also to most surfaces of earth for infrared radiation, because they are almost black in the infrared region.

Bryan,
I was not fully precise. There will be an effect through increased temperature of the body. I meant that there is no immediate effect related to the absorption. For a real surface even this is not quite true, but only a very good approximation, but for a black body it is true.

Pekka
With reference to the option2 and 3 in my post above.
To all realistic intents and purposes there is little practical difference between them.
The heat by calculated by SB equation goes from hotter to colder body.
Option 3 has the unfortunate implication of upgrading the quality of the radiation from the colder object which conflicts with the second law.
Also the possibility of an increase in temperature is a signature of Heat transfer from colder to hotter which Clausius said was forbidden.

There is a curious definitional issue here. A black body is often defined as a body that will absorb all wavelengths of radiation incident upon it. This is a case however in which we need badly to talk about real materials, such as those in the surface of the Earth.

I extensively use a technique called FTIR spectroscopy to identify and characterize materials in my laboratory. The technique commonly uses infrared radiation covering the range from 2.5 microns to 25 microns in wavelength. A material placed on a IR transparent window, such as diamond, is irradiated as the IR wavelength is varied and any absorption results in a scattering of the IR radiation so that much less is reflected back to the IR detector. If real materials absorbed all IR in this broad range of wavelengths, the technique would be pretty useless. The range of IR radiation wavelengths covers most of the spectrum of radiation from a material emitting IR at a temperature of 288K. Near IR spectroscopy covers the longer, low energy tail of the 288 K emitter and while absorption here tends to be greater, it is still much less than 100%. That makes near IR spectroscopy a useful technique also for studying many materials. Most of the Earth’s surface is covered with water and the biggest window for water in the range of IR radiation near that of a 288 K emitter is pretty well aligned with the peak of the emitter spectrum. So water does not absorb all incident IR. Plants certainly do not either. Indeed, we often perform FTIR on plant materials and food products extracted from them. Near IR spectroscopy is also used on plants and food products extensively. FTIR is used less frequently on minerals because they commonly are not very good absorbers.

Sorry. I do not actually do near IR spectroscopy. I should have remembered that it applies to the IR wavelengths in the tail of the solar spectrum, not in the tail of the spectrum of an emitter at 288K. Near IR is therefore irrelevant in this discussion.

Your ‘theory’ of non absorption by a surface of thermal radiation from colder emitters (you don’t say what happens to the incoming radiation), is clearly invalidated by the fact that microwave ovens work, (see Kai’s posts elsewhere). The usual frequency used is 2.45 GHz (wavelength 122mm), your surface at 300K doesn’t emit much radiation at that wavelength! So why does that get absorbed in an oven?
While you’re on here why don’t you explain that when you use your FTIR spectrometer you don’t have to do it in a vacuum because O2 and N2 don’t absorb IR, some of the ‘sceptics’ on here don’t believe that. Perhaps your practical experience will convince them?

In that case, please explain me the approach 2 , and don’t forget Brian was talking about two black bodies.

Now, about Anderson: “why the absorptivity is effectively 0 by a hotter temperature/frequency/entropy body from a colder body “.
You fail to understand that the absorptivity of a surface, which is the proportion of radiation absorbed vs reflected, at a given wavelength, is a constant property of the material. No matter where 15um photons come from (from a cold body, a hot body, a distant body, a shaking body, an “active” body, a “passive” body), the ratio of absorbed 15 um photons is the same.

Another time, you can check easily textbooks for the absorptivity vs. wavelength for all the different type of opaque materials : the position of Anderson is untenable.

Ort
If you look at one consequence of option 3 it means that
100J of radiative energy at centred at 15um is up converted to 100J of radiative energy centred at 4.7um, without any work being done?
This is contrary to the second law.
This is why option 2 is correct.
It satisfies the Stephan Boltzmann equation without violating the second law

For the black body the wavelength of the incoming radiation makes no difference, when the amount of energy is the same. 100J heats by 100J. After the absorption it is in the heat of the body and for that the type of the incoming energy makes no difference, only its quantity in energy units.

As stated by really many writers the black body absorbs also any wavelength whatever its own temperature.

The second law has nothing to say about this. It tells that more radiation goes from the hotter body to the cooler than wise versa. It does not say anything about what happens when radiation hits a body.

“If you look at one consequence of option 3 it means that
100J of radiative energy at centred at 15um is up converted to 100J of radiative energy centred at 4.7um, without any work being done?”

You seem not to understand the Stefan Bolzmann law (radiation of the body occurs, even in a vacuum), and the laws of thermodynamics neither. In fact, your assertion itself is totally confused and erroneous, linking two independent phenomenons with apparently an implicit energy equality (is that what you call “2d law”?) which can not be applied to your body, which is not a closed system! You already had long, clear, detailed, repeated and explanations of this on SoDs site by different contributors, more patient than I am; so it seems I am losing my time.

Ort
“If you look at one consequence of option 3 it means that
100J of radiative energy at centred at 15um is up converted to 100J of radiative energy centred at 4.7um, without any work being done?”

Back to the previous question you included the quote but did not answer the implication.
Instead you ignored it and went into a irrelevant rant.
If the increase in quality of the radiation does not happen then options two and three are the same.
If it does happen the second law is violated.

There is no such thing like your imaginary direct process of “upconversion” by “work”, so, I repeat, your rhetorical question as formulated does not make sense.

Emission of thermal radiation is a function of temperature of the body (and if not a black body, a function of emissivity, a material property) and that’s that. Period.

If ever there is some incoming radiation, whatever its wavelength, it will be absorbed (black body). But no matter if there is or not some incoming radiation from other bodies, and what could be its spectrum, the status of the outside world has no effect on emission of thermal radiation.

Now, in all the possible configurations, if doing the sum of all the energy exchanges (including the radiating ones) between the black body and its environment, you find: E_in > E_out, then the temperature will increase (in function of the mass and of the heat capacity). If E_in<E_out, it will decrease; if E_in = E_out, no change. There is nothing "thermodynamically wrong", here.

With your choice of same energy values (the last case), you tried at the same time to imply an imaginary direct causal link between emission and absorption, by the means of "upconversion", your word. You are supposing that the emission of thermal radiation is due to photoexcitation: you have invented some physics. You are now free to repeat ad nauseam "2d law, 2d law!", but don’t expect another response from me.

Ort
If you read the original post it was the consequence of to the radiation of having the hotter object there as opposed to its absence as it passed through the defined area.
Absent ; 100J at BB spectrum centred around 15um.
Present;
Option 2 no effect on the temperature of the hot body other than to reduce the heat loss from the hot body.
Option 3.
To increase the temperature of the hot body.
The 100J Joules is upgraded to be centred around 4.3um.
This violates the second law as stated by Clausius.
Heat flows from a hot object to a cold object never the reverse.
The increase in the “quality” of the radiation reduces entropy =>against 2nd Law.

If the problem was solved using vectors, there would be a single vector pointing from hot to ciold

The case you cite is different. The incident radiation comes from a hotter source, not a colder source or one of an equal temperature.

When I measure the absorptivity of radiation in my lab, I use a light source with a filament or emitter which is hot compared to the material I am reflecting and absorbing radiation upon. LEDs are pretty cool compared to a tungsten filament, but they are still warmer than the room temperature object being examined for its absorption of light.

Note also that IR detectors image objects warming than themselves, not objects cooler than themselves.

This guy Anderson is a total crank when it comes to the greenhouse effect at least.

First, the whole idea that the ground cannot absorb low frequency light because of vibrational states is complete garbage. The density of states of low frequency motion in a solid (like the surface of the earth) is much higher than the density of high frequency motions. Moreover, the vibrational energies of water and CO2 are several hundred to thousands of wavenumbers. That corresponds to temperatures over 1000 K. You’re telling me that the ground can’t absorb photons corresponding to a temperature of 1000 K? Really?

On top of that fact, what percentage of the earth is hotter than 1000 K? Like the 0.00000001% that exposes lava lakes? So even if the structure of materials like the surface of the earth were such that there was a low density of low frequency motions, the energy from GHG emission could still be absorbed virtually everywhere on the face of the planet!

So this guy can even come up with a meaning, fake physical theory! And you take him at face value?!

Moreover, all this talk about how a colder body can’t transfer heat to a warmer body is only meaningful in the macroscopic limit. Unfortunately, that means when we’re talking about the collisions between molecules, which Anderson does at length, we are in the MICROSCOPIC limit and energy can transfer to a molecule upon a collision, even if that molecule is in a lower energy state. Temperature and heat are not defined for a single pair of molecules, therefore we are not violating the second law of thermodynamics as well! Make an important mental note of this fact.

There are also sooo many collisions happening, that it is very likely energy gets transferred from a kinetically excited O2 or N2 into a state of CO2 or water from which that molecule can decay radiatively. The chances of this processes happening increase as one increases in altitude because collisions become less frequent (density decreases) while the radiative decay rate stays relatively the same. In the stratosphere, the rate can even increase due to increases in temperature.

So all in all, one needs to be slightly more skeptical of these types of claims. To just believe it because it says what you want to hear is not very scientific. In fact, it may be the exact opposite from scientific. Then again, I’m beginning to expect that from some of you.

Does your rant actually refer to Anderson’s paper or to something else? What is all this stuff about 1000 K, e.g.? Where does he say that the “ground cannot absorb low frequency light because of vibrational states?” Maybe I missed something?

if you insist on making a comment, you ought to make sure you have read what the content necessary for such a comment.

From schtick’s comment taken directly from Anderson’s site,

‘The same is the case with some of the low energy, longwave infrared radiation returned from greenhouse gas molecule de-excitations. The Earth’s surface will not accept them since the excitable vibrational states are already excited and vibrating assuming that its temperature has not dropped since the returned photon was emitted by the ground. There simply is no available energy state able to accept it.’

He is saying that there are no ‘states’ that can absorb low frequency IR light because they are already in an excited state. If we ignore the factual inaccuracy of this statement to begin with (excited states still absorb IR light to get to further excited states) he is basically saying that there is an almost permanent vibrational population inversion in where there are more molecules in the surface of the earth that are excited rather than in their ground state. How else could he insist that, on average, ‘low’ frequency IR photons are not absorbed by the surface of the earth? If being in an excited state stops such a process, most molecules must be in such an excited state, right?

Wrong. That is about as nonsensical a statement as one can make. If what he is saying were true, we could make a laser of the earth. I’m not seeing the ‘earth-laser’ in the near future.

On top of that, it’s not as though each molecule only has one excited vibrational state. Each electronic manifold has many, many such states, each with its own selections rules for absorption of IR light or scattering of light. So even if the molecule is in an excited state, it can still absorb a photon of the appropriate energy to excite vibrational population to an even higher lying excited state.

Because we are discussing vibrational transitions on the electronic ground state manifold, we do not have to take into consideration the topology of the potential energy surface itself. That means almost all of the overtones (excited state transitions) are of about the same energy as the fundamental. That means that the energy emitted by the decay from the first excited state will be very close to the energy necessary to make the transition to the second excited state from the first.

That’s a great deal of quantum mechanics, but the point is that his premise is wrong to begin with, so whatever conclusions he makes with it are incorrect.

On top of THAT, since he is discussing temperature, we can ask what the energy in a photon that excites the asymmetric stretch of CO2 corresponds to. Using Einstein’s equation and making an equality with the thermal energy from the Boltzmann constant, we find that such a photon has the equivalent of over 1000 K. When we follow his logic (ground to warm to absorb ‘low’ frequency IR light) it falters on the fact that a negligible portion of the earth’s surface is over 1000 K. Therefore, using his false logic, the vast majority of the earth’s surface should still absorb IR light emitted by CO2 molecules because those photons correspond to a temperature that is much, much hotter than the vast majority of the earth’s surface.

So not only is this guy wrong on the front of the greenhouse effect, he is wrong about the optical properties of molecules and the optical properties of materials like the earth. I’m happy I came across him though. I wouldn’t want his firm doing any work for me. Who knows what he’d tell him.

Can you follow all of that, or should I break it down for you even further?

“The Earth’s surface will not accept them since the excitable vibrational states are already excited and vibrating assuming that its temperature has not dropped since the returned photon was emitted by the ground. There simply is no available energy state able to accept it.”

Which is baloney. He seems to be unaware that temperature is an average, for one thing.

He he your post just made me think of a perfect household example for challenging (imho killing, but let’s see what aswer propoents of the no absorption can come in):
How can my microwave very efficiently heat my food, when it emits (a lot of) photons at very low frequency (2.5 Ghz, 10 cm wavelength, centered around the emission peak of objects much much colder than my food !!!)

Right, in the context of the effective photon temperature, this definitely defeats Dr. Anderson’s theory. The photons have an effective temperature below 100 K (I think) while the food is at room temperature.

MW cookers are tuned to excite water molecules. That’s why the handle of the coffee cup is barely warmed while the liquid contents are strongly heated. I haven’t tried it, but I assume it would be hard to MW-heat Melba toast!

MW ovens heat materials with a strong absorptivity at the frequency of the oven irrespectively of the fact that the wavelength is long and the frequency far below the range of IR where the body emits most efficiently. In this respect there is no difference compared to the situation where long wavelength IR heats a hot body, whose emission peak is at much shorter wavelengths.

For the heating to happen we need radiation at any wavelength where the absorptivity is high. For the heating power the total power flux of the radiation is the determining factor, the wavelength is of no significance as long as the absorptivity is high. The temperature of the body has little influence on the absorptivity.

PP;
your English comprehension skills have failed you. Obviously I was talking only about absorptivity, and made no suggestion that it varied with temperature. But many materials (ceramics and glass, fortunately) are almost transparent to the MW’s Magnetron’s output! I assume, of course, that H2O’s absorption is related to its fingerprint wavelength. Is that not so?

In any case, your point does appear to me to contradict CP’s assertions. My understanding is that the 2nd Law relates only to net energy transfers between bodies at different temperatures. However, the RATE of cooling of a hot body would be lower if another object of intermediate temperature were inserted near it, warmer than the background. If it were colder than background, it would block some “incoming” IR and speed the hot body’s cooling. IMO.

One thing I think we miss is that one of the bodies should be passive (with no self-heating) if we’re creating an analogy to CO2 in the atmosphere. Can radiation from a passive body return heat to a hot body and make it hotter? It can affect the hot body’s rate of cooling, but it cannot make it hotter.

it has to do with the energy balance. At thermal equilibrium, we are defining that the energy leaving a body is equal, on average, to the energy coming in. It seems like a stretch for the earth’s surface, but let’s make the assumption for argument’s sake.

So the earth’s surface is at thermal equilibrium by absorbing visible light from the sun and emitting IR light back to a mostly transparent atmosphere. Now we begin to add molecules to the atmosphere that can absorb the IR light emitted by the surface of the earth and, upon radiative decay, emit IR light back toward the surface of the earth. We have now changed the energy balance of the earth’s surface by adding MORE energy in. In response to this energy increase, the earth’s surface increases in temperature so that it can emit MORE energy to come to a new energy balance. This new thermal equilibrium is at a higher temperature than the previous equilibrium.

I have a night storage heater which has a dial to increase the energy input and therefore increase the heat output. When it gets really cold I turn the dial up to get more heat out, but this cost me more money in energy.

Now thanks to your brilliance I have just worked how I can save myself a small fortune. I don’t why it never occurred to me before but then thats why we have superstar-scientists like you, so we don’t have to think for ourselves right?

Thanks to your genius I have realised that all I have to do is open up the front panel and stuff some more bricks in it. Then I will have changed the energy balance by adding more energy in.

I think you’re confused as to the analogous relationship between your heater and the earth. In fact, I’m certain of it.

By adding CO2 to the atmosphere, we’re changing the energy balance OF THE SURFACE!

Those are two different systems. You’ve taken this distinct, squashed and mixed concepts in your example to create a incorrect assessment of the possible energy balances and imbalances at the earth’s surface.

Okay, Maxwell, I’m listening. Let’s imagine 2 black balls floating in space. One has an internal heat source and a constant temperature…the other is passive and a long ways away. Now we move the passive ball closer and closer to the active ball. Closer…closer…closer, then so close they touch.

During this process, what does the temperature profile of the active ball look like? At any time, is its temperature measurably greater than it was when the passive ball was far away?

Well, Fred, here’s what I see. Joe Sixpack reads the headlines and saw An Inconvenient Truth, so he believes in global warming and thinks the earth will experience greater and greater temperatures because of increased CO2 concentration in the atmosphere. He thinks the earth’s peak temperatures are increasing and more and more temperature records will be broken as we SUV-boogie ourselves into blackened crisps.
Now Fred, you and I know it takes a certain amount of energy to heat up the active ball to a certain temperature and, in order for the active ball’s temperature to increase…additional energy must come from somewhere. And, we know the passive ball will not add energy to the active ball.
So, Fred, hit me with your best shot. I’m particularly interested the instant just before the balls touch when they are infinitely close, but not touching, then the instant after they touch each other.

You didn’t answer my question. How will a correct answer to your own question affect your thinking about the greenhouse effect? If it can be shown that the active ball will warm, will that change your mind about the greenhouse effect? If not, why not?

I don’t want to waste my time, so I need a commitment from you before I take the trouble to give an explanation.

That depends on what you mean by “shown”, Fred. If all you have is a formula or a theory or a weblink, then I’m not going to be very influenced. If you have test data, taken in a vacuum, that shows a passive object measurably increasing the temperature of an actively-heated object purely via ‘backradiation’, then I will rethink my life’s mission to attack and kill the sky dragon.

Ken – think about it a bit more. It’s late, but we could probably continue tomorrow. I have not floated any black balls in space recently, so you’ll have to do without “test data”. It’s actually very easy to show via principles that we all agree on that the active ball will warm. I’m prepared to do that. My own dilemma will be the following: suppose Ken claims that he is not convinced, for whatever reason, but it is clear that other readers of this thread without a stake in the outcome will find the explanation convincing, and will judge Ken accordingly for his refusal. Should I go ahead?

Well, we’ll see. That might be enough for me to proceed, knowing that perhaps someone else’s “life mission” will be profoundly altered for the better.

Ken,
You say: “in order for the active ball’s temperature to increase…additional energy must come from somewhere.”
and “And, we know the passive ball will not add energy to the active ball.”

That is not true. There is no doubt about the fact that the passive ball will add energy to the active ball as long as the passive ball is not as cold as the empty space. It will add the more energy the closer it is until it is brought into contact. At that point conduction enters and it starts to cool the active warmer ball through conduction.

Pekka
……”That is not true. There is no doubt about the fact that the passive ball will add energy to the active ball as long as the passive ball is not as cold as the empty space. It will add the more energy the close”……

An object (at say 200K) can only raise the temperature of another object if the temperature of the other object is less than 200K
If the other objects temperature is > or = to 200K its temperature cannot be increased by the first object.

ok, one last time: The temperature of the hot object is not increased by the cold object, it is increased by whatever heating mechanism made it hot (internal heater, the sun which is a much hotter object, a maser, pick yuor choice).
What the cold object does is reduce the cooling efficiency of the even colder surrounding of the hot object. Reducing this cooling efficiency allow the heat source (remember, pick your heating mechanism of choice, but in case of earth, it is the sun) to heat the hot object some more, until equilibrium heat_in = heat_out is once again reached, only at a higher temperature.

Really, it is so simple that I think there is a (selective and deliberate?) blind spot that prevent some to consider the external heating, who think somehow that all the heat have to come from the cold object. Nobody sane has ever clamed that a cold object will radiatively heat a hot object if there is not third object or some kind of ohter heating mechanims in the hot object, not for any though experiment, and not for GH effect for the earth.

I actually think we’re making progress. I am an engineer, so naturally I think in terms of getting useful work done and what can be practically measured and verified. Also, as an engineer (and not an academic), I get to discount small effects that are irrelevant to the job I’m trying to do.
If my job assignment was add heat an already heated ball, would I use a passive ball to do it? My boss would fire me for spending any time on that plan. If the effect can’t be measured, then it is something of the theoretical realm and not the practical realm. I don’t care about the theoretical realm…in that world there are billions of influences and arcane aspects to consider. Getting bogged down in them would make me a bad engineer…a slow and expensive man to work with.
So, how effective, in theory, can a passive ball heater be compared to a heated ball? Radiation is a crummy way to couple heat energy, but we’re in space and that’s all we have. My heated ball is radiating in three dimension (actually, four I guess if you allow the passive ball to modulate the heated ball’s temperature). As the passive ball is far away, how much radiation is it intercepting? It’s also radiating in three (or four) dimensions, so how much can it return? Let’s call it none.
We move the ball closer. The passive ball gets slightly warmer. It radiates a bit more. Let’s skip ahead to where things get interesting.
The passive ball is as infinitely close to the heated ball as it can be without touching. The straight line coupling between the closest point on the heated ball and the passive ball is infinitely short. That point on the passive ball is as close to the temperature of corresponding point on the heated ball as it can be. Let’s say, at that point only, the temperatures are equal. So, at that point what is the delta-T? And, at that point, what is the radiation intensity?
Now move away from that point of maximum coupling. The temperatures diverge, right?
I didn’t mention the relative ball diameters, but I don’t care. Let’s call them equal. Visualize it. Visualize the cone of radiation from the heated ball radiating the surface of the passive ball. How much? Not much. Now visualize the return radiation from the passive ball. How much of that cone intersects the heated ball? Not much. So, how effective is the heating created by the passive ball? A tiny fraction of outgoing heat energy coupled by radiation gets returned. It’s so close to zero that you can’t measure it. So, in the case of two balls coupled as much they possible can be…zero. Then they touch and conduction massively overwhelms anything radiation can do. In this case we say the action of conduction is the opposite of the action of radiation…and I’m not sure I buy that, but I’ll think that through later.

You say radiation from the passive ball heats the active ball. I think I agree in theory. But I don’t care about theory. I care about the real world. Due to errors of measurement and noise, you can’t measure and quantify the temperature increase. Once you live in a world where you’ll believe in things you can’t measure…you’ll believe anything.
For example, you’ll believe back radiation from materials with low density, low temperature and low thermal mass (like atmospheric CO2) can heat things with high density, higher temperatures and larger thermal masses (like sea water).

A single passive ball, Ken, would not heat the active ball very much, as you state. However, a very large multitude of passive objects completely surrounding the active ball, equivalent to a…. well, an atmosphere, would cause significant heating.

That’s what your formulas and models tell you, Fred. You believe it. That’s fine.
However, even the slightest, tiniest error in evaluating insolation and its linkage to surface temperatures would swamp out all the influence (and more) you attribute to 390PPM of CO2.

The atmosphere is being heated back by the surface. If the surface is warmer, it’s warming the atmosphere more than it is getting back. Continue until equalized, at which point Fair Trade takes over and no change occurs.

Think of the passive ball as a reflector of radiation – well it isn’t really, but the effect is the same as far as the active ball is concerned.
The active ball is being heated by the source, but at the same time radiating energy. The energy it radiates is energy lost.
But some of that radiation is reflected off the passive ball and is so returned to the active ball, which means that the active ball doesn’t lose as much energy as it would were it not for the presence of the passive ball.
As the temperature of the ball will increase while Eout is less than Ein, the active ball gets hotter.

Assuming an infinite temperature detection precision, I’d say that that both balls gradually get warmer as they get closer. When they touch, we’d have to know the heat conduction properties of the materials from which the balls are made.

But before such a point, however, each ball is taking in energy (from conduction from the internal heat source and from radiation) and emitting energy via radiation. As they approach each, more of the energy emitted from each ball is being absorbed by the other. Therefore, we are changing the energy balance of each ball. In response to changing this balance, the balls increase in temperature so that they can create a new balance by emitting more energy back to space and each other.

Yes, I’m with you. You have not convinced me the temp difference in the active ball is measurable and I’m still a little puzzled about how energy is conserved in this system, but that’s okay.

I think you guys would have been okay…you could play with SBL and radiative balance and study back radiation and had great, quiet academic lives…but the activists wanted to change the world and found you to be useful academics. The tough times you guys have coming is collateral. That’s unfortunate. On the other hand, you had your chance to denounce An Inconvenient Truth and the worst of the exploiters like Schneider, Trenberth, Hansen and Mann…and you were silent.

‘You have not convinced me the temp difference in the active ball is measurable…’

We’d have to know the amount of internally supplied energy and the distance between, etc., but I’m not convinced we would measure it either.

More dramatically, however,

‘…but the activists wanted to change the world and found you to be useful academics.’

What are you talking about? I’ve never talked to an ‘activist’…well, besides you. I think that’s a totally inappropriate thing to claim when 1) you don’t my name, my work or even my opinion about climate politics 2) I am being as level with you on the topic of discussion here. I am not accusing you of anything illicit or demanding that you act in accord to my particular political beliefs on specific issues.

You’re right, Maxwell. You’ve been polite and helpful and I do appreciate it. I’m a bit revved up right now and that’s not your fault. My editorial comments were uncalled for.
In fact, to go even further, I will publicly apologize and send a $100 donation to the charity of your choice when you show me where you’re on record criticizing the alarmism and activism of An Inconvenient Truth. Fair enough?

I’m a bit busy today, but the quote below is good enough for me. I apologize to you Maxwell and I will send $100 to DwoB (and prove it).

Usually figures like JFK jr and Al Gore are cited as people to believe or whose opinions on scientific matters are of value. It’s a bit depressing to me to so transparently see the newsroom editor’s bias, but that’s the way it goes.
–Maxwell at A Few Things Ill Considered

Indeed some of them are published PhD scientists who are extremely sceptical of claims that claim to overturn well established and tested science like CJ (who has still avoided a calculation based on his theory). Not to mention claims that N2 and O2 can absorb IR in contravention of all measurements!

Claes, I have read your chapters, your comments here, and your blog post. There’s no maybe about it: you’re a crackpot. Physics departments around the world ocassionally receive manuscripts claiming to overturn 100 years of physics by misusing classical equations. Unfortunately your work reeks of this and the many, many selected quotations (Abe Lincoln?) don’t help. This is neither silence nor ridicule, just straight talk.

Thermally excited gas molecules in the atmosphere will radiate, even at night. Some of it will be directed downwards. This is your so-called “backradiation.” It should not require any equations to convince you of this.

Temperature is a statistical phenomenon corresponding to the average kinetic energy of a collection of particles. As many people above have patiently tried to explain to you, there will always be some molecules in a body ready to absorb an incident photon of the right wavelength, even if that photon was emitted by a body with a lower temperature.

These are basic phyiscal princples. If you don’t understand them all the equations in the world won’t help you. It’s like buttoning a shirt; you’ve put the first button in the wrong hole.

“Thermally excited gas molecules in the atmosphere will radiate, even at night. Some of it will be directed downwards. This is your so-called “backradiation.” It should not require any equations to convince you of this.”

David,

like others before you on this thread you have confused downwelling radiation with “backradiation”.

These two are not interchangeable atmospheric parameters that you can flip between at will. They must be separately defined as follows.

Downwelling radiation contributes NO net energy increase because it is energy which is already present in the system.

Back radiation MUST be accompanied by a demonstrable and measurable net energy increase.

Will, the document you linked to does not contain the word “downwelling,” so I’m afraid I found it of little use. Your comment raises other questions. Like, if something is measurable, is it not also demonstrable?

Some radiation leaving Earth’s surface will be absorbed by the atmosphere, and some of that will be emitted back towards the surface. This results in a smaller net heat loss than if the process did not occur. But it does.

the link is to a paper which demonstrates that there is NO net increase in T since 1975 in the unadjusted Radiosonde data which is accurate to 0.1º C. Unlike the surface record which has an error margin of 1.3º C and is, provably, arbitrarily adjusted to fit the AGW narrative at will.

The smaller net loss argument MUST be accompanied by increasing temperature above and beyond the natural signal. It has not been.

Furthermore your smaller net loss argument is falsified by the fact that adding CO2 can only increase atmospheric transmission to space not decrees it. This is substantiated by the Radiosonde data from the paper in the link I gave you. And has been demonstrated experimentally by myself.

That’s up to you but your experiment is not relevant to AGW unless it meets the requirement I stated. So if you wish to have any credibility you’d better answer the question. Otherwise we’ll have to conclude that either you don’t know the answer or are hiding the truth.

Will, the paper you linked would be much improved if it included citations for statements like: “There is no radiative heat transfer from SST to atmosphere.” A paper prepared for publication would include such references. Anyway that statement is false. I stopped reading at that point.

Regarding your experiment, on the contrary, I applaud it, and the effort. I have some criticisms however. The main one is that the 1 deg. C effect is probably smaller than the error of a fishtank thermometer. I’d like to know other things, like was there the same volume of water in each bottle and what was the tempurature of the water.

Ah but I am discussing the matters at hand Kenneth. His statements and the concepts behind them. Have you really not seen that? Johnson has a lot of ideas that have no foundation, such as statistical thermodynamics doesn’t explain reality and physics can’t be explained with words. And when you call him on it, he deflects. That’s a crackpot.

No, he’s not trying to explain. And he’s not being polite. “At least I use Maxwell’s equations.” Like I don’t? And he can call me a crackpot all he wants but it won’t stick, because I’m not the one going around saying statistical physics is bunk based on ignorance plus a misinterpretation of something Einstein said a century ago. But please, ignore all that and keep focusing my blunt language.

He’s attempting to overturn the science behind radiational heat transfer which demonstrably works in practical situations. The onus is on him to show that his formulation correctly explains observations without invoking radiation from the cooler body. So far he has avoided doing so.

Claes,
Equations are meaningful only when they are applied correctly. Anybody can write equations and make claims (and on these issues very many have indeed done that claiming almost anything imaginable), but without proper connection to the physical situation this is meaningless. Explanations that you have presented in your texts are almost always obscure, sometimes simply contradictory. With good will and some favorable interpretation some of them can be found to be correct, but in many cases this is not possible. Therefore your use of equations does not prove anything.

But you don’t base it on Maxwell’s equations. You say that the electric field is \ddot u , the acceleration of an oscillating charge.
But J C Maxwell said that the electric field is determined by
Div E = Q .
Maxwell’s equations don’t appear at all in your chapter.

You really need the Maxwell-Bloch equations, which we’re available when Planck was around. You have to account for sources the EM radiation. The wave equation on its own won’t do the trick because we know we have sources in the atmosphere, as confirmed by over a hundred years of lab experiments.

The fact that you are not considering sources is likely why the solution you find is ‘unstable’.

Have you calculated the macroscopic polarization of the atmosphere under steady state conditions? If not, I’d say you don’t know what you’re doing.

Claes, that is nonsense. Equations are shorthand for words. I’ve explained two concepts concisely. If my words cannot be contradicted by observation or experiment, then no further words–or equations–are required.

These data is the base of both thermodynamics and Radiative Heat Transfer. However, it seems the advocates of the “downwelling” radiation heating up the surface and of the pretty-exaggerated “backradiation” don’t want to take them into account.

The emissivity and absorptivity of air at near-surface pressures is very high (close to unity) in the relevant wavelengths. Those are the wavelengths at which surface IR is absorbed and emitted by greenhouse gases – in particular, CO2 and H2O. Emissivity/absorptivity values outside of those wavelengths are irrelevant. To put it another way, the atmosphere is very far from being a black body in general (e.g., compared with a Planck distribution), but behaves like a black body in those parts of the spectrum where it is optically thick. This accounts for its strong greenhouse effects.

Fred, for having a near 1 emissivity, the air pressure would be at least twice the real pressure and its temperature should be about 5000 R. Attributing unreal exaggerated physical characteristics to air is the “error” of AGW idea. Almost all books on heat transfer and radiative heat transfer show the numbers I’m including here.
You know the purpose of the those air bubbles in packing bags is, and my post shows why.

That’s not correct. The relevant emissivity is at specified wavelengths. For example, the atmosphere is optically dense at 15 um, such that almost all IR emitted from the surface is absorbed (and emitted isotropically) within a short distance above the surface (probably a few tens of meters or less). If the atmosphere had high absorptivities/emissivities at all wavelengths, the Earth would melt. The values at the specific wavelengths are what account for the strong upwelling and downwelling radiation within the atmosphere itself.

These values are incorporated into the radiative transfer codes used to compute the effects of CO2 and H2O on the vertical temperature profile of the atmosphere. The computed results match observational data quite well.

Of course they are, and the article refers to an emissivity of unity at the absorption maximum for CO2. I believe you should revise the descriptions on your website to conform to real world emissivities that are relevant to greenhouse effects. Emissivities described without reference to wavelength are essentially meaningless in this regard. It is certainly acceptable to mention them, but after that, you should then cite the emissivities in the IR wavelengths of relevance to the greenhouse gas absorption spectra. These are very high.

No, they are not… Begining from the fact the formulas they applied are not the adecquate formulas.

The formulas I applied for my calculations are the same formulas derived from experimantation by many physicists.

I suggest you, Fred, to visit the references I give in my website cause their authors support what I say in my article. No where, in this world, I mean the real world, we have a 0.04 atmospheric water vapor with an emissivity of 0.7, neither a blackbody CO2. The numbers I provide are real, coming from experimentation, they are not the outcome of idealized systems.

it is common knowledge that reflectivity, emissivity and absorptivity are all frequency dependent parameters of any gas, liquid or solid. Given that these parameters are fundamentally based on quantum mechanics and the structures of each gas, liquid or solid is different, these parameters HAVE to depend on frequency. That’s why the index of refraction of a material, from which ALL optical properties of a material can be derived, depends on frequency.

Not exactly because such a collection would not absorb at all frequencies, but it would be much closer to a blackbody.

Furthermore, the sun is a collection of ionized nuclei floating under a sea of electrons, interacting in such a complex manner we are basically mystified at what the sun does most of the time…but the output of that complex collection of atoms, nuclei, electrons and plasmas puts out a distribution of energy that looks a lot like a blackbody spectrum.

There are gradations in questions and understand that you have to neglect in order to get the result you want. I’d say that’s not science.

“These values are incorporated into the radiative transfer codes used to compute the effects of CO2 and H2O on the vertical temperature profile of the atmosphere. The computed results match observational data quite well.”

Then why has there been no warming for the last 15 years? Where is the “match?” Something must be “overshadowing” these effects (or they don’t exist). What?

I assume that you concede that the data does not support “catastrophic man made global warming?”

First, let the scare mongering stop and then we will start taking about “limit, control or consent…”

a) Where did I mention catastrophic or scary anything? Is this some explosion of the ‘disturb’ question to unintended proportions?

b) This accusation of scaremongering you toss about so defamatorily and so easily when simply questioned about your statistical methods and opinion of the scale of the numbers you provide, how is it meant to be productive?

c) Concede based on your arguments and presentation? Yours are some of the weakest and most transparently prejudiced claims I’ve seen on either side of the debate, frankly; while I’m going to go out on a limb and avere that I remain skeptical of many claims on both sides and find some claims on each side well worth studying, your claims in particular do not excite in me cause for concession. More.. the urge to return to my old teaching mode and attempt to address the errors in an energetic and interested scholar because they are so grating.

You have elected a troublingly brief and complicated dataset to rest your ‘proof’ on.

I am seeking the traditional guidance from you of an audience for an analyst.

There is over a century of data you have excluded from your analysis. Please explain why.

Your initial point is suspect due to extrinsic conditions many have observed about it before when used elsewhere by others, for example its known oceanic cyclic effects. Please explain how you meet these objections.

Your dataset has, relative to its range, a large error bar; how do you handle this?

Many others have done analyses on the same data. Please walk me through two or three such analyses from each side of the debate, other than your own, comparing your techniques and conclusions to theirs, so I may put your claims into context and judge your ability to critique on the subject.

Or at least answer even one objection or criticism from any honest student of mathematics about why you so abuse statistics to subjugate so obviously to your preconceived opinions?

One of the first computer programs I wrote as a student relied on data from a table in a textbook.

It was a total failure. Try as I might, I could not make the program work.

No matter what I did, the computer’s arithmetic logic came to a different conclusion than this table, which had been used for many years and reproduced in scientific literature over and over again, so must be right.

Well, it will not stop untill the warmers, lukewarmers, almost warmers, etc. can find some EMPIRICAL EVIDENCE for an “atmospheric greenhouse effect.” That means at the very least a CORRELATION between GHGs and temperature. There is NO SCIENCE HERE! No falsifiable hypothesis. No data, only models. NOTHING! Radiation cartoons and GCM’s are not empirical evidence. Nor are endless IR spectra. Nor are temperature measurements (which are going the wrong way–so sorry to report this to the true believers). Nor are endless arguments among physicists, as is occuring here. We need clear EMPIRICAL evidence of an increased warming due to CO2. It has not been forthcoming, and probably will not in the future. We cannot even explain the RWP, Cold Dark Ages, MWP, LIA, let alone the Modern Warm Period (if there is really one after considering all the disgusting “adjustments” made by NASA and CRU!)

Back to the drawing boards, you warmistas! The king has no clothes on!

Please assist me in addressing your request by providing examples of the empirical evidence and standards you used to accept or reject (validate) this evidence for “..the RWP, Cold Dark Ages, MWP, LIA,..”

As your screed stands now, it either uses a new definition of the word ‘clear,’ or is self-falsifying.

If you don’t need data, then it’s certainly not going to qualify as evidence to a scientist. I can think of no case where a history text qualifies as empirical evidence, except possibly if one is testing the paper for the concentration of dioxin compounds or the ink for inclusions of mercury.

If you would accept history texts, but reject arbitrarily Dr. Seuss and other works of similar merit and veracity, one must conclude you have a double standard.

Further.. not to malign co2science.org too much, but the same argument applies. The interpreters of the reports compiled there have a known bias, their interpretations carry this bias, their data selection carries this bias, so one must be more, not less, skeptical of information caught in the halo of prejudice.

When looking at the proxy candidates proposed by the various reports collated by these biased interpreters, one finds none within one sigma of that of the present temperature record, and most appear to be of the same CI or lower of commonly proposed evidence for the opposite of the interpreters’ claims.

In the case of multiple conflicting poor reliability datasets, and a readily available group of better reliability datasets, what reasonable person would do as you have urged and reject the better reliability data to embrace the worst ones?

Your post is a stream of consciousness like meander through several aspects of thermodynamics, an incorrect assessment of solid state physics and engineering tidbits…but there is nothing in it all that raised my eyebrows with respect to the Stefan-Boltzmann law.

I mean, you state that it’s not applicable in all situations, which I admit, is a shocker. But everything else is basically innuendo.

Most entertaining was the statement,

‘Heat transfer by radiation is really only applicable to a vacuum.’

Apparently you’ve never sat by a fire or a space heater. You’re really missing out.

Jen: thanks for that link. Maybe, hopefully, it will cause some of the know-it-alls out there to review the facts. Maybe not, since there are so many that are so committed to their “facts” that they cannot objectively look at alternative “facts.” Until we have some kind of clear evidence of a CAGW problem, we should not let a bunch of crazed environmentalists ruin our world. If those folks did not smoke so much pot, I would trust them more :-)

JAE:
“……we should not let a bunch of crazed environmentalists ruin our world.”

There’s plenty enough to be skeptical about without having to denounce the basic science of the greenhouse effect. I feel that you are very much in the minority of the denizens (who are predominantly skeptical after all). In itself, that’s nothing to worry about but it might give you some pause for thought and a more careful consideration of what is being said.

When you calculate the slope (trend in our case) of a profile, the start and end points must be between successive local maximum and minimum.

Perhaps the best evidence for global warming is the extraordinary lengths to which skeptics have to go in redefining science.

The reason the temperature has those peaks and troughs is because of the ocean oscillations. This is spelled out with a closed form formula for the violet curve in this graph, which closely tracks the actual temperature.

The terms in the formula for the violet curve are based on the observed behavior of the ocean oscillations along with the Arrhenius formula for temperature as a function of CO2, and the Hofmann formula for CO2 as a function of time.

Fitting trend lines the way you’re doing it is simply playing with meaningless straight lines that make no attempt whatsoever to understand what causes the temperature to behave the way it does.

And hopefully 2030!

Your naively drawn trend lines may well say that, but a more careful analysis suggests that 2030 should turn out to be around 0.4 °C hotter than 2010.

Your naively drawn trend lines may well say that, but a more careful analysis suggests that 2030 should turn out to be around 0.4 °C hotter than 2010.

Science is based on validated on theory. Your theory say “2030 should turn out to be around 0.4 °C hotter than 2010”. (0.2 deg C warming per decade)

I, a vehement and proud man-made global warming denier, say “2030 should turn out to be around 0.3 °C COLDER than 2010”.http://bit.ly/cO94in

How about this: If your projections are closer to the observation, we accept man-made global warming. If the skeptics projections of slight cooling is closer to the observation, we reject man-made global warming.

What is wrong in advocating the accepting or rejection of a theory only after comparing projections with observations?

What is wrong in advocating the accepting or rejection of a theory only after comparing projections with observations?

Nothing whatsoever. You fully expect the temperature to go down over the next 20 years. I fully expect it to go up over that period. If in 20 years time the temperature has gone down by 0.3 °C with no other evident cause than simply the failure of the global warming theory, then I would join you in rejecting the theory of global warming.

An example of an “evident cause” would be an asteroid or giant meteor or megavolcano throwing up so much dust or ash as to blot out the Sun long enough to greatly lower the temperature relative to what science projected. If that happened then it would be unfair to reject the theory of global warming on that ground.

If you are given the following global mean temperature pattern, what would be your projection for the next 20 years?

I don’t base projections on data alone, and I don’t base them on theory alone either. Until the data and the theory support each other, at least one of them must be wrong. Until you’ve figured out which of the theory and the data is to blame for the discrepancy, you can’t trust either and therefore projections from either are meaningless.

In the case of the red curve you ask about, what’s the theory behind compressing, detrending, and offsetting? Without knowing that it’s impossible to predict what the next 20 years of it would look like. It’s like asking what’s the next number in the sequence 3,5,7. If you said 9 I’d say “wrong, the next odd prime is 11.” But if you said 11 I’d say “wrong, the next odd number is 9.”

You can’t make reliable projections from raw data without an underlying theory. Correlations may give some idea, but they’re trumped by theories of what’s causing what and that are consistent with those correlations, like the competing odd-prime and odd-number theories of the data 3,5,7.

In the case of the HADCRUT3 data, there exists a theory that is in good accord with the data. I therefore don’t have to trust either one of them by themselves. The black curve labeled Residue accomplishes two things. Because it did not stray far from zero over the last 160 years, it tells me that theory (the violet curve) is in good accord with the data (the red curve, smoothed to remove short-term events that are irrelevant to long-term global warming). But because it does fluctuate by up to 0.05 °C with rare excursions beyond that, it also tells me not to place too much trust in the violet curve in placing bets on the future since it may off by 0.05 °C and I’d lose that particular bet.

Long term however, as long as the black curve continues to behave as it’s done for 160 years, I would end up ahead if I used the violet curve as a betting guide.

And it is at least plausible that the black curve will stay roughly within those limits for at least the next 20 years.

It’s certainly more plausible than any of the many straight lines you seem to think count as a model. None of the physical phenomena contributing to long-term global temperature are well modeled by straight lines, so there is no point trying to make straight lines fit somehow to the data. The ocean oscillations are reasonably well modeled as sinusoids (that’s why they call them oscillations) while the CO2 contribution is a “log of raised exponential” shape as per the theories of respectively Arrhenius and Hofmann.

In the case of the red curve you ask about, what’s the theory behind compressing, detrending, and offsetting?

Detrending is done to clearly see the oscillation component of the global mean temperature. The linear warming f 0.6 deg C per century removed by the detrending can be added latter to the oscillation component. As a result, the detrending does not remove anything from the global mean temperature.

Compressing removes short-term noises from the data.

Offsetting is just a translation and does change the data.

Again the following global mean temperature pattern was valid for the last 130 years, and it is reasonable to assume the pattern will be valid for the next 20 years. This means that we will have global cooling until 2030.

2) “I think we have been too readily explaining the slow changes over past decade as a result of variability–that explanation is wearing thin.”http://bit.ly/aMJ6OQ

3) “The scientific community would come down on me in no uncertain terms if I said the world had cooled from 1998. OK it has but it is only 7 years of data and it isn’t statistically significant.” [This statement was made 5-years ago and the global warming rate still is zero]http://bit.ly/6qYf9a

4) “The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t.”http://bit.ly/7jJE0X

No one doubts the existence of global warming or global cooling. Both have been occurring for billions of years. What many doubt is the absurdity of catastrophic man-made global warming (still unproven) triggered by minuscule emissions of a life-giving atmospheric plant food.

And your claimed 73.32 G ton of CO2 for 1998-2010 is impossibly low, even just for 2010 alone it was 30 G ton! The correct figure for 1998-2010 is 356 G ton. You’re as far off as Ferenc Miskolczi when he got a figure for the kinetic energy of the atmosphere that was a factor of five too low.

When arguing against global warming you may find it safer to avoid arguments with numbers in them. You and numbers don’t seem to get along very well.

Your understanding of climate is also nonexistent. You appear to be unaware of both the 56-year Atlantic Multidecadal Oscillation and the 75-year or so Pacific Decadal Oscillation, which have drifted into phase in the past century to create large swings in global temperature that pretty much completely masked the CO2 warming prior to 1980. Only after 1980 did CO2 reach a sufficiently high level to start sticking out like a sore thumb.

I think the issue is that you are talking about CO2 weight and Girma is talking about Carbon weight and unwittingly wrote CO2. I freaked when I saw your 30GT figure and looked it up. I am used to the 8GT figure also but it is for C not CO2!!

I’m not sure what’s troubling you here. Earth’s atmosphere has a mass of 5.148 * 10^{15} tonnes, and the area of the Earth is 0.510 * 10^{15} m2. Hence per square meter the atmosphere weighs about 10 tonnes. If you think this arithmetic is wrong then please supply the correct answer. This quantity, 10 tonnes/m2, is needed in computing how long it takes 0.53 kW/m2 to raise the temperature of the atmosphere by one degree.

Due to the 3dns problem the “state of art “GCM substitute the third full ns equation with the hydrostatic approximation.The trade off for this is idealized geometry ie equal meridians of longtitude and latitude and a surface area of 500 mk^2.

I didn’t understand all that, but in any event you still haven’t said what the correct answer is.

A pressure of 1 bar or 1000 hectopascals (= millibars) is exactly ten tonnes/m2. The actual atmospheric pressure at the surface of the Earth is generally reasonably close to 1 bar, and varies somewhat, making ten tonnes a reasonable figure for the mass of a square meter of atmosphere. I truly don’t understand what you’re complaining about; all we’re trying to do here is estimate about how long it will take 0.53 kW/m2 to raise the temperature of the atmosphere by one degree. I get a little over 5 hours. If you get something different then tell us what you get instead of just complaining about what you believe to be errors.

Restating 1998-2010 for carbon instead of CO2 reduces the 356 figure to 97 GtC. The number 73.32 GtC is for the period 1998-2007.

In any event, not taking ocean oscillations into account is guaranteed to give strange results. The combined amplitude of the two ocean oscillations during 1910-1940 is around 0.12 °C (so a total swing from trough to peak of 0.24 °C), which accounts for more than half the swing from 1910 to 1940.

Here’s a budget for each of the following two 30-year periods, based on the formulas and graphs given here.

AMO denotes the temperature rise caused by the two ocean oscillations. CO2 denotes the temperature rise caused by GtC emission. AER denotes aerosol or other induced cooling or warming, typically with warming resulting when there are fewer volcanoes. TOT is the sum of these three temperature rises. GtC is the gigatonnes of carbon emitted during each of those 30-year periods.

The oscillations are drifting out of phase and therefore their sum is weakening.

GtC is increasing and therefore so is CO2-induced warming.

Aerosol/other cooling/warming seems to be rather random.

The upshot is that the total temperature rise for each period is somewhat similar, 0.42 °C vs. 0.47 °C.

Note that the GtC had to rise by nearly a factor of 6 to get the CO2-induced temperature rise to merely triple. That’s the Arrhenius logarithmic law at work.

See the budget immediately above. The relevant formulas for ocean oscillations and CO2-induced warming are attached to the graph. The aerosols-and-other is everything not otherwise accounted for, which seems to have at least some correlation with volcanoes and perhaps aerosols produced during WW2 in blowing up entire cities.

So you don’t dare post the warming rates for the period from 1910 to 1940 & for the period from 1970 to 2000?

I thought you claimed you are good at numbers!

What are those two numbers?

Please no obfuscation.

This is the claim of the IPCC:

For the next two decades, a warming of about 0.2°C per decade is projected for a range of SRES emission scenarios. Even if the concentrations of all greenhouse gases and aerosols had been kept constant at year 2000 levels, a further warming of about 0.1°C per decade would be expected

The current decadal global warming rate for the decade is less than 0.2 deg C per decade.

The current decadal global warming rate is even less than the 0.1 deg C per decade projection for the case if CO2 emission had been held constant at the 2000 level.

@Girma As this is what the data says, why the alarmism of man-made global warming, as similar magnitude and duration warming had happened before — naturally?

I answered this here. The bottom line is that while the two numbers are almost the same, as you point out, they have very different causes. Whereas the first is mainly due to the upswing of a natural ocean oscillation, the second is mainly due to the exponentially increasing anthropogenic component of CO2.

The reason to be concerned about the latter and not the former is because oscillations average out to their center line whereas exponential growth keeps increasing. The oscillations have been going on for centuries, whereas exponentially growing CO2 is an entirely unprecedented phenomenon.

I just finished reading a tome on quantum mechanics. (no I can’t do the math, popularization by a physicist) Based on my reading of his statements anyone trying to argue quantum mechanics better get out the Ouija Board!!

If Claes actually understands it well enough to use mathematics rather than statistics, few are going to approach it.

Well, I don’t understand Claes well enough to even comment, so I’m trying my best to shut up. I’m just a chemist. Color me dumb, if you will. But I have a strong hunch that there are a lot of know-it-all blowhards, here , and most especially at Lucia’s site, who also don’t understand him, but won’t admit it and are joining in the mob-mentality of bashing him, without ANY frigging facts! I will bet anyone a six-pack that the “opponents” are nothing but bare-assed progressives.

that is a misapprehension I am under also. I was under impression that everything emitted IR also based on temperature. You are talking about GHG’g bond IR which is a different thing. Can you refer me to some physics text that will assure me that what you are saying is true??

My understanding is that larger molecules have more transitions so do have wider bandwidths for their planck energy than gas molecules. That does not completely remove the idea that gas atoms may emit also, only that their bandwidth will be limited.

that is a misapprehension I am under also. I was under impression that everything emitted IR also based on temperature. You are talking about GHG’g bond IR which is a different thing. Can you refer me to some physics text that will assure me that what you are saying is true??

To absorb/emit in the IR a gas molecule needs a dipole, homonuclear diatomic molecules don’t possess a dipole and therefore can’t do so, N2 & O2 good examples and also monatomics like Ar. A linear, symmetrical triatomic like CO2 doesn’t have a permanent dipole but because it has a vibrational mode which bends the molecule it has a temporary dipole which does allow it to absorb/emit. Isotopologue molecules like N^14N^15 will show some very weak lines (~10^6 times weaker than CO2).
You can read about it in any text on Molecular Spectroscopy such as the ones I referred to above: Herzberg (the bible), Harris & Bertolucci, Barrow etc.

The only way that si well developed and known to work includes back radiation.

I should work harder at promoting my theory based solely on those photons that escape from Earth to space. It neatly finesses the complexity of back radiation. The main reason it can do this is that we know what the temperature of the atmosphere is at all altitudes and therefore do not need to calculate how back radiation influences temperature; we just need to know it’s retained in the atmosphere as opposed to escaping to space.

In any event heating the atmosphere requires about 10 megajoules/m2 to raise the temperature of the atmosphere 1 °C, since the constant-pressure specific heat of air is 1.01 kilojoules/kg/deg and 1 m2 of atmosphere weighs about 10000 kg (10 tonnes). Even if we ignore the 0.531 kW/m2 flowing out of the atmosphere (333+169+30 W/m2), the 0.532 kW/m2 flowing into it (356+78+80+17 W/m2) will take 1.01*10000/.53 = 18800 seconds or over 5 hours to make a one-degree difference in a column that can easily vary by 70 °C from ground to tropopause. Taking into account the 0.531 kW/m2 flowing back out means that the changes are even slower. (Notice their difference of 1 W/m2 or 0.001 kW/m2 representing the non-equilibrium condition responsible for actual global warming.)

Temperature variation in the atmosphere due to lapse rates of 5-9 °C/km therefore completely dwarfs anything that GHG heating can do in the available time to change the temperature of the atmosphere. Global warming certainly heats the atmosphere, but it does it very very slowly, taking days or weeks to make any appreciable change.

This is a big part of the reason why one can completely ignore back radiation and work solely with the photons that escape to space, which ultimately is Earth’s only way of keeping cool. The photons that leave are gone within microseconds, those that don’t leave take days or weeks to have any appreciable impact at all on the temperature of the atmosphere, which therefore is more than adequately modeled by the adiabatic lapse rates alone without worrying about the impact of back radiation on temperature across the whole column of atmosphere.

Vaughan,
I was referring to the state where the basic physics has developed. By basic physics I mean things like quantum mechanics and theory of electromagnetic radiation. General relativity is also part of that although not needed here. Classical thermodynamics is a bit different, as it does not go into the actual physical processes but expresses laws that apply to macroscopic bodies. Thermodynamics is also different in the way that it can be derived from what I classified as basic physics, but not vice versa.

There is very much physics that describes macroscopic phenomena, but cannot be fully derived from basic physics, while physicists believe that it could be, if we were more capable in calculating the consequences of basic physics. The description of the atmosphere contains much that can be derived from basic physics, but also much that cannot. The subject of this chain is more or less in the first class.

Claes Johnson presents ideas and calculations that are clearly in the realm of basic physics. Part of what he presents is in agreement with well established and tested physics, part is clearly in contradiction. What makes his presentations a bit difficult to handle is that the second of them contains also parts, which might be correct or not, as they are presented with little justification, but they might indeed be related to an alternative way of describing valid physics. The idea of using classical electrodynamics (Maxwell’s equations) further than is usually done is not crazy. It might even work, but that would require much more research and the conclusions would certainly not be those presented in “Slaying a Greenhouse Dragon”.

If there is anything at all in this line of reasoning (it still needs to explain observed radiative fluxes), Johnson needs to submit this to a peer reviewed physics journal, and not publish in a politically motivated book that is full of crankology. His argument at present is incorrect and incomplete.

JC: ” a politically motivated book that is full of crankology.”
Wow-such insults!! Judy, please explain to all what my political motivations are? I can confirm several of the book’s authors, like me, hold explicitly democrat/socialist affiliations.
Also please tell us where the “crankology” is in the book? If the insults are as a result of your buddies doing so badly perhaps its now time for you to call in your A-Team – those “undergrad physics or atmospheric science majors at Georgia Tech” who you assured us at the outset would soon prove Claes a crackpot.

John, if you are only in this for the science, you are backing some very strange and lame horses. Apologies for being fooled regarding your political affiliation: I was fooled by your engagement with Canada Free Press – billed as an online conservative newspaper- and National Review.

Something like this could in principle be published in a physics journal as a theoretical development. But a more coherent argument is needed, cleaned up math, and it has to be correct and provide new insights. This seems to fail on all these fronts. I suspect that this would be published in a journal like E&E, which doesn’t even merit an impact rating by webofscience.

Lots of different kinds of research get published, including critiques of other people’s papers. Getting published is a pretty low bar; of course getting published in a high impact journal has a high bar. E.g. I’m sure Johnson could get his paper published, just not in a physics journal or in any journal that is on the map in terms of impact factor

While I try (emphasis on “try”) to avoid labeling people, I’d say that the following by you at your blog is pretty badly wrong. I’ll let Judge Judy decide whether that makes you something less than a Nobel-prize-winning scientist.

Is it correct to use SB in the form Q = sigma T^4? No, because this law gives the radiated energy from a blackbody into an environment of 0 K. But the Earth surface is not at 0 K, but even warmer than the atmospheric emitter. The translation Q = sigma T^4 is thus incorrect in the sense that it indicates a fictitious “downwelling IR flux from the atmosphere” obtained by an erronous translation.

This isn’t how Stefan’s law works. Radiation from any source does not decrease merely because what it is radiating into is radiating back to it even more strongly. It is completely independent of what it is radiating into.

Vaughan,
I hope I am not causing additional confusion by what follows.

The radiation can be looked at in the standard way that you and more all less everybody uses with visible light and IR, but almost nobody with low frequency radio waves. The radiation can, however, be analyzed as is done with the radio waves using Maxwell equations. In that approach the matter interacts with electromagnetic field and the field follows Maxwell’s equations. The gas is handled as media where the field propagates. The interaction with CO2 molecules influences the properties of this media and those modifications can be presented in the coefficients of Maxwell’s equations. This influence must represent correctly in accordance with quantum mechanics the vibrational properties of the molecules. In this approach the whole concept of photon may be superfluous. Building up this theory without violation with quantum mechanics may be difficult, but probably not impossible. There is even a change that, what Claes Johnson has done is a partially correct step in this direction. That is the reason for my way of presenting criticism and objections to what many others have written.

In this approach the back radiation is replaced by some properties of the media which lead to a similar change in net radiative flux. In this approach there is no back radiation but a reduction in “forward radiation”.

Claes,
Perhaps I understand something, but that makes me to repeat, that the question is about an alternative formulation that must give the same results than other correct formulations. I have great trust in the conventional formulation. Therefore your analysis does not make me doubt the conventional results.

Including this kind of incomplete analysis in a politically motivated book attacking on correct science does not give value for your work. The other problem with your writings is that they contain so many sentences, which are either clearly in error or so obscure that nobody can tell, what you want to say.

But your model does not support heating by radiation that are at a lower freq than some cut-off frequency linked to the receiver T. This is a fundamental difference with classic theory.

How do you explain microwaves within your framework? They seem to very efficiently heat stuff at room temperature with very low frequency waves (2.4 GHz, 10 cm wavelength usually). If I get your theory right, such feat should not be possible because the cut-off at room T is much much higher than 2.4 GHz.
Or are you willing to invoque some coherence argument because the magnetron emit maser-like radiation instead of thermal stuff? Does not look too solid to me, and I am affraid you are getting dangerously close to experimental invalidation of your theory ;-)

The general description about a potential new approach has no problems with that.

I cannot really answer on behalf of CJ, but I noticed that his statements about separating incoming and outgoing wavelengths were softened in formulas to the cutoff of the Planck distribution. This is one place were his text is worse than his formulas. There are many other examples and they make it impossible to judge, what he really thinks.

Could you elaborate on this? What do you theory predict? possible heating, or all the incoming low freq radiation can not be absorbed (i.e. it is either reflected, diffracted, or plainly reflected)?

If it is absorbed, I do not see how your theory significantly differ from classic theory, and all the fuss is about interpretation (still, I prefer classic interpretation, which offer a big advantage: the radiating body does not need to know the exterior temperature)

If it is not, why does microwave oven obviously work? Because there is a fundamental difference if the incoming waves are coherent single frequency? Then your theory has another disadvantage: it is less general, because it works only for thermalized radiation, and does not allow independent freq treatment or any kind of superposition….

No problem: it is included in my analysis. If the incoming
forcing is stronger than blackbody, the absorbing chicken will heat up until its blackbody radiation (assuming equilibration so that all freq have the same temp) balances
the incoming intensity.

Pekka, my problem with this line of reasoning is that any theory of infrared radiation needs to explain what an IR spectrometer sees when pointed skyward in a cloudless atmosphere. This seems to have nothing to do with a reduction in “forward” radiation.

Judith,
That is not a problem in the alternative description. In this description electromagnetic field is present everywhere and its development follows Maxwells’s equations taking into account the influence of the media (gas with some CO2). When a measuring device is brought to such electromagnetic field it interacts with the field in full accordance with the empirical results observed.

The CO2 molecules influence the field and the field interacts with the detector. All this is familiar at longer wavelengths but it is true also for short wavelengths. The most practical way of performing the calculations varies, but the basic theory is the same.

Judith,
I do not think that Johnson has done much of what I have described. I said only that there are some similarities and that the basic approach is not wrong. It could possibly be developed to provide many results in a rather simple way, but I doubt whether it would really add anything to the understanding of the atmosphere.

If further research along these lines is to produce interesting science it is more in understanding quantum mechanics and quantum filed theory than in understanding the atmosphere.

This is why I started my comment above by “I hope I am not causing additional confusion”.

For a theoretical physicist this line of discussion has some similarities with the argumentation between “orthodox” climate scientists and their skeptical critics. Criticism should not be condemned because it is on unfamiliar lines, but it can be discounted when found erroneous or lacking all justification.

I understand your point and it is a good one, but I suspect John O’Sullivan and Ken Coffmann do not understand the nuances of your position. But I also suspect that your willingness to consider this approach provides credibility to your statements in the eyes of O’Sullivan and Coffmann.

Judith,
The numerous possibilities of misunderstanding my position have led me to repeat many times that nothing in what I have written contradicts the conventional approach. It is only an alternative way of describing the same physics.

By back radiation I understand radiation that originates in the atmosphere and hits the earth surface (or some other surface facing the sky near the earth surface). The radiation affects the net energy balance of this surface in the same way in both descriptions. In the first description the net flux is the difference between the energies of all outgoing (emitted) and incoming (back radiation) photons. In the second description the same net energy is transferred to the electromagnetic field, which then carries it further.

I don’t really think those are two different approaches to this problem. Saying that one approaches uses photons while the other uses waves is just that, saying it.

Physically those two processes are indistinguishable. One can go through the process of counting each photon for fun or one can solve the Maxwell-Bloch equations to find the wave equation with sources. It’s still the same physics, however.

I think that’s the thing that is confusing here. It sounds like you’re saying there could be a physically distinct way of thinking about this problem that produces the same result (IR emission toward the surface by GHG’s), but supplies that result via a macroscopic vs. microscopic perspective, ie EM waves vs. photons. But our current physical understanding is that these two concepts are the same physical phenomena, just allowing us to interpret the results of different kinds of experiments differently.

But even if you went for the EM wave approach, you’d have to do quantum mechanics to calculate the elements of the density matrix to correctly calculate the macroscopic polarization of the source of the EM waves. So those two approaches are not independent in any sense. They just look different to the untrained eye who is willing to blather on and on about Maxwell’s equations.

If Dr. Johnson is proposing that there is some inherent physical difference because he’s solving Maxwell’s equations for macroscopic systems, he’s wrong. It’s still the same physical approach solving for the exact same physical quantities.

In my opinion, he is not even solving the right Maxwell’s equations because he will neither confirm nor deny whether he has derived the wave equation with or without sources of EM waves.

So I think to continue on this track that Dr. Johnson COULD be on to something important if it confirmed observations is hazardous, not only because he is fundamentally incorrect, but also because there would be nothing new about his deriving the macroscopic approach to the situation.

Maxwell,
By two different approaches I mean that the same fundamental equations are solved in very different ways. I have tried to repeat often enough that there is only one physical theory behind these two approaches, but the mathematical handling would be really very different.

The standard approach at the deepest level starts with perturbation theoretical methods of quantum electrodynamics and uses immediately Feynman diagrams to help in writing the required lowest order terms. This is known to be a very good way of doing quantitative calculations. The results can easily be expressed in terms of emission and absorption of photons originating at some positions and ending up at some other. It includes also transitions between vibrational states of CO2 etc.

The other approach has been used in laser physics where fields are relatively strong and coherence is an important factor as is stimulated emission, but not to my knowledge in situation corresponding to atmosphere. The extensive incoherence of separate transitions and almost full nonexistence of stimulated emission makes this approach rather useless for detailed analysis. My idea is that it might still be a potential alternative for handling atmospheric radiation. The approach would involve certain approximations not present in standard approach, but perhaps these approximations could be shown to be acceptable.

The mathematics is definitely different, and the approach is therefore not a minor modification of the standard method. Still the aim would be to solve the same basic equations with the expectation that the results are the same.

As far as the two approaches go toward a meaningful end, I think you would agree with me that there is not a mathematically or physically distinguishable difference between the perturbative approach using quantum mechanics (either quantizing the field or treating it classically) when applied to atmospheric spectroscopy and the implications of spectroscopy.

There may be some high field limit in which, because of plasmas or other exotic forms of matter, there is some wave formalism that adequately describes what happens. But given that is a completely physically distinct situation, I think we would both agree, on the terms that Dr. Johnson is trying work, such a limit most likely does not matter.

kuhnkat,

I could waste a couple paragraphs explaining how you are mistaken in your understanding of the current standing of modern physics, but it would be just that, a waste.

And the absence of CO2 in that analysis by Pekka speaks volumes as to where our book is coming from; the need for the IPCC’s politicization of a trace gas and to isolate CO2 in this process is superfluous, sinister and invalidated by Occam’s Razor. After a quarter of a century and $100 million spent trying to single out CO2 as a forcing agent we not only see no empirical evidence to substantiate the GHE we no longer see any correlation between temperatures and CO2 levels in the atmosphere (outside the period 1975-1998).

John O’Sullivan,
The potential approach that I have described is influenced by CO2 to the same extent and from the point of view of physics in exactly the same way as standard theory. It is only formulated differently in doing the calculations.

I believe that I was the first one to use the formulation “politically motivated attack on correct science” about your book in this chain. I have no reason to doubt the correctness of this formulation – or do you propose that it is published purely for the advancement of science?

Judith predicted that you will not be able to understand, what I have written. Evidently she was right in that.

” an IR camera (infrared radiometer) directed to the sky measures the frequency of incoming light and computes by Wien’s displacement law the temperature T of the emitter, and then by Stefan-Boltzmann’s law Q = sigma T^4 associates a “downwelling IR-flux from the atmosphere” of size Q.”

Perhaps addressing this statement would be a good place to start Judith.

This statement is absolutely incorrect, it if is referring to gases in the atmosphere. Gases emitting IR from the atmosphere are not black bodies (they emit in spectral bands), and hence the integral form of the Planck function (e.g. the Stefan Boltzmann) law is not relevant.

Do you see why I despair of critiquing this stuff? It is a hydra monster, you clarify ten things, then you start over and have to clarify these things all over.

Sorry but I have not observed much clarity in your responses to me so far.

When a communication channel breaks down because the receiver can’t keep up with the transmitter, the blame could in principle be shared: the receiver for being too slow and the transmitter too fast.

In practice one specifies a rate for the channel, and the fault then lies with whichever end is out of spec: the receiver for being too slow for the channel or the transmitter for being too fast for it.

In this case Judith is both the transmitter and (as blog host) the specifier of the channel rate. So if you can’t keep up and she’s not willing to lower the rate just for you, I would suggest hanging out on blogs that are more your speed.

This statement is absolutely incorrect, it if is referring to gases in the atmosphere. Gases emitting IR from the atmosphere are not black bodies (they emit in spectral bands), and hence the integral form of the Planck function (e.g. the Stefan Boltzmann) law is not relevant.

A more precise statement might be that Stefan’s law is relevant only to the extent that the spectral bands are distributed reasonably uniformly across the bulk of Planck’s function at that temperature. The integral of Planck’s function is still Stefan’s law when you punch holes uniformly across the whole curve. It’s only when the spectral bands die away or stop abruptly, both being common behaviors, that Stefan’s law breaks down in any serious way.

Although I’m way outside my league in terms of background in theorical physics, I’ll have a shot on this: if I’ve understood correctly, what has been written above about the alternative way of calculating the radiative energy in the form of radiowaves and Maxwell’s equations, this calculation is done to analyze the propagation of radiation and hence energy into certain direction; the source of radiation would be the surface of the earth, and the medium the athmosphere.

What you see from the spectrometer pointed skyward is the another direction; the source is the atmosphere.

Anander,
Maxwell’s equation describe electromagnetic field, which fills all space, but may vary strongly from place to place. When the wavelength is very short the equations lead to the result that the source (the emitting molecule) and the sink (the detector) must essentially have a free line-of-sight connection. Very short waves turn very weakly around corners, but this is a property of the solutions of Maxwell’s equations.

On the other hand we do not observe individual CO2 molecules. According to the Copenhagen interpretation what is not observed is not determined. Thus there is no deed to handle the atmosphere as a collection of molecules with well defined positions but it can be handled as a field of molecules, which interacts with the EM field. This is the approach of quantum field theory.

The standard description of what happens corresponds to the lowest degree perturbation theory described by the simplest possible Feynman diagrams that have the required interacting components.

In your opinion – is it correct to say, that this approach (i.e. modeling the radiative transfer as fields and ultimately translating it into flux in/flux out) should and would lead, if correctly applied, to same results as the more standard way of doing it with fluxes (S-B)?

And if, when using this alternative way to model the radiative transfer, one finds out that there is either none or very little downwelling ‘backradiation’ one has probably just made some error along the way rather than a scientific breakthrough?

I admit I didn’t read the book either, and possibly wouldn’t understand (at least all of it anyway), but for me dismissing the effect of above zero-K gas above us is just insane — of course it matters. What is written here I get a feeling that is at least to some extent the central message out there.

IMHO we can at least calculate a reasonable average ballpark figure for the strenght of the backradiation given the composition and distribution of different gases and their relative temperatures. The main source for my sceptism (and probably for many others, too) is how this translates into changes in global climate as the change (just the change in dw radiation) itself is anyway quite small.

The standard description of atmospheric physics is valid and there is no need to modify it. If two alternative descriptions are presented for the same physical situation then either they agree or at least one is in error. In this case the standard description is based on very solid knowledge and is with great certainty valid. If a new little studied alternative gets different results it is almost certainly in error. If the presentation is in addition incoherent and vague, the new results cannot be taken seriously even if there are some good ideas in the first steps of the new approach.

All that I wrote above applies to that part of climate physics, where the basic equations can be applied in a straightforward way. The validity of the rest must be argued differently and taking advantage also of additional empirical observations.

No, you may only include my quote in the context of the entire statement. If someone says backradiation does not exist, then I have no idea what they mean since some of the infrared emission from CO2 and water vapor in the atmosphere does travel back in the direction of the Earth’s surface.

Can you specify exactly how much of the re-emitted IR actually reaches the ground and how the probability of that changes with altitude and with regard to the curvature of the Earths surface. And how that reduction in probability by increased altitude of the re-absoption at the surface is factored in to the “greenhouse effect” hypothesis?

That’s a great question. I stepped outside just now and measured the backradiation from directly above reaching my deck at 210 W/m2. About 60 W/m2 of that would like be due to water vapor (it’s a dry sunny day) and 150 W/m2 to other GHGs, in particular CO2.

On cloudy days when it’s about to rain it’s more like 350 W/m2 (and that’s in winter at 37° N, you can expect a lot more at the equator). At least 250 W/m2 of that if not 300 would be from the clouds and associated water vapor, with only 50-100 W/m2 coming from other GHGs besides H2O.

The reason there’s less from the CO2 is that the clouds are blocking more than half the downradiation from the CO2.

The bottom line basically is that trying to figure out how much back-radiation reaches the surface is really complicated.

And completely unnecessary since backradiation is an unnecessary distraction when trying to figure out how much any given increase in CO2 can warm the Earth. Backradiation is nothing more than an indication of the general temperature of the sky above you. That temperature varies hugely with altitude, cloud cover, etc. Here in Palo Alto in winter I’ve seen it change from 10 °C to −40 °C in a mere 12 hours.

But given that the atmosphere gets colder with altitude, at a rate between 5 and 9 °C per km depending on how wet or dry the air is, even the huge fluctuations measured on the ground still don’t give the full picture of the thermal complexity of the atmosphere because you can’t measure lapse rate just from the ground. Trying to figure out the quantity and distribution of backradiation is tremendously complicated and a needless headache.

It is much easier instead to work with Earth’s goal of constantly shedding 239 W/m2 from the top of the atmosphere, which is the amount of insolation it is absorbing. Increasing atmospheric CO2 acts to shut off progressively more CO2 absorption lines in the atmospheric window. At 288 K, the middle 50% of that window is from 468 to 993 cm⁻¹, and at 390 ppmv about 600 CO2 absorption lines in that region are closed. Each additional 2% increase in CO2 closes about 3 more lines. CO2 is currently increasing at about 0.5% a year, so every 16 months sees another line closed. By 2060 that rate will be down to 8 months a line. CO2 has 25,000 lines in that region so there is no danger of running out of lines to close.

Closing does not happen abruptly but quite gradually with increasing CO2. I like to define a line as closed when it is blocking the escape route to space of more than half the radiation at that wavelength from the Earth’s surface. More commonly people use 1/e rather than 1/2 as the criterion but it’s somewhat arbitrary exactly where to draw that boundary; using either 1/2 or 1/e, about 3 lines close with each 2% increase in CO2.

Are you saying that closing lines prevents CO2 from emitting after gaining collisional energy and that H2O and other GHG’s can’t emit either?

Actually it’s the opposite. A line is open when it is too weak to interact strongly with radiation at that wavelength, both by absorption and emission; it’s as though there were no CO2 at that wavelength. When a line closes, CO2 then both absorbs and emits at that wavelength.

Other GHGs that don’t have a line at that wavelength don’t get involved with that CO2 line. From the point of view of radiation at that wavelength it’s as though those other GHGs weren’t there at all.

The open CO2 lines are those that are not strong enough at the current CO2 level to block at least half the photons from going straight from the surface to space. Most of the open lines let almost all of their photons through to space. They close like a very slowly closing water tap: as they get near the closing point the flow slows and pretty much completely stops after a while. The choice of half as the dividing line between open and closed is arbitrary; climate scientists prefer 1/e rather than 1/2 as the dividing line. Unity optical thickness of any medium through which radiation passes is standardly defined as when 1/e of the photons are getting through that medium. Ordinarily it is defined separately at each wavelength: a medium may have optical thickness 1 at one wavelength while having 0.1 at another and 10 at yet another.

I see, so the energy ends up in the local area and convects up to where it will radiate to space like the energy from the normally closed lines.

Sort of. Radiation, convection, and conduction are all happening at all points, and the huge variability of clouds and water vapor, and the diurnal heating and cooling of clouds by the Sun, all make it unmanageably complicated to say what “the energy” is at any instant, or to say where exactly it’s going: it’s going off in all directions by all possible means. And even though radiation moves at the speed of light, the high thermal mass of the atmosphere in combination with the very low rate at which global warming shifts the atmosphere’s overall thermal equilibrium gives convection and conduction more than enough time to participate along with radiation in gradually adjusting the overall general temperature of the atmosphere.

The advantage of limiting the analysis of global warming to the 239 W/m2 of Outgoing Longwave Radiation (OLR) Earth must send to space to maintain equilibrium with the incoming 239 W/m2 of insolation is that that part is considerably simpler than the way heat moves around between the atmosphere and the surface. In fact we really only need to divide that OLR up according to the two places from which it was launched.

(a) The surface, via the atmospheric window (the part of the spectrum not blocked by some line of some GHG). Knowing which lines are closed (and for greater precision, by how much they’re closed) would make that part simple to calculate, were it not for clouds, which being essentially opaque to all relevant thermal radiation from Earth’s surface shut down the whole atmospheric window. But that’s fairly easily dealt with by determining what percentage of time the window is closed, for which there is quite enough data to make a good estimate.

(b) The atmosphere, via closed lines of GHGs which being closed both absorb and emit. The more of a particular GHG there is in the atmosphere, the higher the origin of those photons that make it to space because of the additional GHG molecules that now block the exit to space from lower molecules. However the higher the origin the colder the emitting molecule, and hence the lower the rate at which photons at any given wavelength are emitted from a molecule.

The photons that don’t make it to space are simply ignored as being part of what keeps the atmosphere warm, which as I said involves very slow processes which are therefore best analyzed from the point of view of an atmosphere that is basically in equilibrium albeit with large fluctuations.

So to summarize, wavelengths that are open (i.e. part of the atmospheric window) allow the most photons with that wavelength to leave for space. As any given wavelength is gradually shut down by increasing the GHG responsible for it, the OLR at that wavelength shifts from Earth-originating to atmosphere-originating. But as the GHG continues to increase, instead of the atmosphere-to-space photons of that wavelength increasing (as even some who should know better have claimed here), they decrease because they have to come from progressively higher and hence colder molecules, which radiate fewer photons of that wavelength (and of all other wavelengths but here we’re focusing on a single wavelength).

As a caveat, this de-emphasis of back radiation in explaining the greenhouse effect is a personal preference of mine and not the generally accepted approach which is to make back radiation the heart of the explanation of the greenhouse effect. Some day I’ll figure out how to explain my version more succinctly and clearly. A graph or two of how these processes depend on the level of the GHG in question would probably help, as would weaning the experts off the standard explanation if they ever come to find it more attractive than the back radiation approach.

The back radiation or the alternative formulation the same physics are describing a real effect that increases the temperature of the surface. Making this effect stronger by adding CO2 to the atmosphere rises the temperature further. This an unavoidable direct consequence of higher CO2 concentration. Further changes – the feedbacks – cannot be fully determined from basic physics. The problems are too complicated for that.

Warming is a relative term. You get more heat from infrared radiation emitted by the atmosphere to the surface if you add more greenhouse gases.

The Earth’s surface (usually) emits more infrared radiation from the atmosphere than it receives. Exceptions occur in the polar regions when you have a temperature inversion and cloud that is warmer than the earth’s surface (the topic of radiative transfer in the polar regions is the topic of my Ph.D. thesis and several decades of subsequent research). Purely from infrared radiative transfer considerations, the net infrared radiation balance at the earth’s surface is cooling (again, exception when you have a cloud that is warmer than the surface). The net infrared radiation balance is less negative if you add more greenhouse gases.

Again, the Georgia Tech undergrads understand this. It is pretty simple. This has been demonstrated empirically an endless number of times (see especially the data at http://www.arm.gov). Infrared radiative transfer models have been developed that reproduce these observations under relative warm vs cool atmospheric temperatures, and high versus low amounts of water vapor.

Is an alternative explanation of the basic underlying physics that explains these observations possible? Sure. Has Claes Johnson accomplished this? No. Even if he did, he would need to explain these same observations; the radiative flux and the surface received from the atmosphere by infrared emission from gases such as H2O and CO2 that is observed isn’t going away by some manipulations of Maxwell’s equations.

It seems that while Johnson can do mathematics, he does not understand anything about gases (included spectroscopy and basic kinetic theory).

Judith: Here’s my question. In the summer on the Great Plains, the humid warm air from the Gulf plays “tag” with the cool dry Artic air. One day the air is dry, one day it is humid as heck. Now, when the soil is dry as toast (no evaporation going on), it is absolutely no hotter on a clear humid day than it is on a clear dry day. With all the backradiation from the water vapor, it should be hotter on the humid day. Why isn’t it? Now, puleeeze, don’t ignore the daytime and start talking about nighttime, like everyone else does.

It depends on the wind speed, the details of the atmospheric temperature and humidity profiles. You have to consider both the solar radiation and the infrared radiation. With this kind of information, you can interpret what is going on with the surface temperatures. This is simple.

As I understand the greenhouse gas concept, ON AVERAGE it should be hotter on humid days in July on the farm near Sterling, Colorado than on days when it’s dry. That is not the case. Something appears to be wrong with the greenhouse gas hypothesis, since we are talking about changes in greenhouse gas concentration (water vapor) from about 0.4 % water vapor (5 gm-3) on dry days to 1.6 % (20 gm-3) on humid days.

This is what drives me nuts about climate science: it seems to be all based on completely unflasifiable hypotheses. Any empirical evidence that questions the “science” is automatically arm-waved away, just like you just did. There are always “other things” that keep one from validating any part of the grand scheme.

Judith, in fact he cannot even do mathematics. The equation he starts from (4) has exponentially growing solutions, exp(t/gamma), so blows up rapidly, and so is physically meaningless.
He then makes an integration by parts error, before eqn (5), transferring time derivatives of u in a space integral.

PaulM: You are off track. I am very familiar with the math I present and have written many articles and books on this stuff.
Your objections doesn’t make any sense. How many math articles have you written?

Claes, i read what you wrote, and it makes no sense to me (nor did this section of your article). Tell me, does your theory explain the observation that if you point a radiometer upwards at a cloudless sky, that it will measure a radiation flux of say 200-400 W m-2 (depending on ambient atmospheric temperature, humidity, etc). Can you put the atmospheric profile of temperature and gases into your equations and calculate the flux that is observed? If not, and you continue to insist that your theory is correct, then you get to wear the crank label. You need to clearly address this issue. This is how theories are tested, with observations. There is an enormous amount of data at http://www.arm.gov against which to test any theory of infrared radiative transfer. So how does your theory pass this test of observations? It hasn’t been tested, right? And you somehow think your theory is better than the theory that actually explains observations. Sorry, nobody is buying this. I suspect that even John O’Sullivan and Ken Coffman understand that you have to test a theory with observations. While this can be very difficult to do on the scale of the entire planet, it is very easy to test infrared radiative transfer against observations in a single column.

I’ve described this previously. First, i have no idea what people mean when they say “back radiation”. The emission from molecules in the atmosphere is isotropic (goes in all directions), with some of this radiation going in the direction of the earth’s surface. This is what actually occurs; what you call it is up to you.

So when you point your radiometer skyward what you are measuring is the energy present in the atmosphere which keeps it in its gaseous state.

This energy is therefore energy which is already in the system. What you have failed to show is that this energy is being added back to the sum total as a result of a composition change in the ratio of CO2.

That would require that you can show a clear historical correlation between CO2 and temperature. There simply is no such relationship as you well know. Therefore there is no “greenhouse effect” signal from CO2. Let alone an AGW signal.

As a climatologist I would expect you to acknowledge this point as a serious problem in the ‘greenhouse effect” hypothesis. I would also expect you to wonder if there maybe some doubt in the basic physics on which this hypothesis is based.

I woud also expect you to question why in the last thirty odd years of practically unlimited public funding, the entire weight of scientific genius as failed to devise a simple real world experiment which can demonstrate the warming effect of a change in air composition by increasing the ration of CO2. And why this theory still clings to a 150 year old set of experiments by one man which have never since been re-eximend to analyse the possible flaws.

Your unquestioning faith in the “greenhouse effect” hypothesis of CO2 is breathtakingly worrying to hose of us who can see that you have failed to acknowledge any of these points.

The “greenhouse effect” hypothesis requires that a substance with highly transmissive properties like CO2 ultimately behaves as an insulator restricting the net energy loss to space.

Judith it would be fantastic and truly astounding if that were the case. But it isn’t.

When you understand and finally acknowledge all the negative feedbacks such as I have listed in : http://www.spinonthat.com/CO2_files/CO2tdino.pdf which more than compensate for any possible positive transmission warming effects you might realise just how dangerous and far of the mark, the “greenhouse effect” hypothesis really is.

I tried looking over your paper but I have a general rule about papers that begin with a Hitler quote. Sorry.

CO2 admits short wavelengths and absorbs long wavelengths. That’s what makes it a greenhouse gas. Even if CO2 is not responsible for recent climate changes it still contributes to the total greenhouse effect. Or are you refuting the entire greenhouse effect?

“I tried looking over your paper but I have a general rule about papers that begin with a Hitler quote. Sorry.’

That is the best excuse for a short attention span I have ever heard!

“Or are you refuting the entire greenhouse effect?”

As a sub-surface dweller, I do refer to surface warming as a “greenhouse effect”, for the simple reason that it is a fallacious concept that could be used for nefarious purposes, such as that which occurred with the so called “science” of eugenics.

it might improve the conversation if we tightened up this description. The so-called back radiation is a wave or probability front expanding around the emission point. There is a good reason to use this explanation rather than the assumption that there is an actual particle that leaves the emission point with a specific vector.

One of these days I may even be able to explain this good reason to another person.

Judy: Ask your students to explain to you that an IR-meter measures frequency (this is why it is called and InfraRed-meter), and that the connection to “downwelling radiation from the atmosphere” is ad hoc
by applying SB in the form Q = sigma T^4. If you claim it is not ad hoc
then prove to me that the formula applies. Or ask your students.

Actually, an IR-meter measures intensity at one or more frequency bands in the infrared portion of the EM spectrum by filtering out or otherwise being insensitive to frequencies outside the desired measurement range.

Heck, you can point an IR spectrometer upwards and observe the spectrum of the radiation from the atmosphere, so all this back and forth, is, as they say sausage. THEN you can point the IR spectrometer downwards and you can ACTUALLY MEASURE the amount, if any, of reflected IR from the downwelling radiation. HINT: Almost all of it is absorbed because, if nothing else, the absorbtivity/emissivity is close to unity for most materials in the region of the IR being talked about.

JC: “I suspect that even John O’Sullivan and Ken Coffman understand that you have to test a theory with observations.”
Yes, even a’ dumbass’ like me knows that! So why, after 25 years and $100 million spent can you and other ‘ clever climatologists’ not give us one experiment in the atmosphere to prove your faux theory?

Heh, I provided some observations above somewhere that seem to me to contradict the concept that backradiation adds to surface heating, and all I got was some hand-waving that didn’t even speak to my observations.

That is what is so slippery about climate science: nothing appears to be falsifiable, and if you bring up some observations that don’t fit the hypotheses, you are just told that there are “other variables” that make your observations nonsense or that you are just dumb (which cold be the case, of course). Now, we are even getting stupid statements about the snowstorms being caused by global warming (although mainly by idiots like Gore and the news media. I don’t think any reputable climate science has chimed in on this. Yet. However, tellingly, the famous climate scientists are sure not going out of their way to dispell this crap, either).

Will | February 2, 2011 at 10:17 am |
The specific frequencies that 99% O2 and N2 absorb emit at are filtered out.

Such a device would be worse than useless if that was not the case.

They aren’t filtered out because they don’t exist, if you persist in this in the face of documented evidence you aren’t a sceptic you’re in denial!
See here: http://www.siliconfareast.com/FTIR.htm
“Unlike SEM inspection or EDX analysis, FTIR spectroscopy does not require a vacuum, since neither oxygen nor nitrogen absorb infrared rays. “

highest order IR absorption selections rules are based on the presence of a permanent electric dipole or an electric induced dipole (in the case of the asymmetric stretch of CO2) in a molecule.

Both N2 and O2 lack a permanent or induced dipole upon the excitation of the single, totally symmetric stretch possible. Therefore, due symmetry based selection rules, the absorption of IR light by N2 and O2 is negligible. O2 has a small, but non-zero magnetic dipole because there is an abundance of the paramagnetic form of O2, but the absorption cross-section for that transition is exceedingly small and can be ignored for most practical purposes.

CO2 only has a temporary dipole moment. A temporary dipole moment is induced in O2 and N2 by ionisation which is occurring at varying degrees throughout the entire atmosphere.

Ionisation is most prolific in the Diurnal Atmospheric Bulge which covers an area of 25% of the Earths atmospheric surface under the solar point and bulges upwards to an altitude of 600 km.

Some people refer to the Diurnal Atmospheric Bulge as the Thermosphere. But it is not a sphere it is a bulge with a circumference equal to 25% of the surface of the atmosphere and bulges up to an altitude of 600 km. The ionisation is so intense that the bulge is actually elongated towards both poles due to the magnetic forces involved, (the Diurnal Bulge or Thermosphere, as you may know it better, disappears below the Mesosphere at 100 km on the dark side of the Earth).

ummm, according to sources, the ionization potential for N is over 14 eV. That corresponds to a photon with a wavelength of less than 100 nm.

That’s well into the vacuum ultraviolet region of the EM spectrum, bordering on the extreme UV region. The solar spectrum counts off pretty effectively at less than 5 eV.

The ionization potential for N2 is actually HIGHER than atomic nitrogen because the presence of the other nitrogen atom reduces the kinetic energy of the electrons relative to the molecule’s scattering states.

Now, should we believe some speculation about the behavior of the earth in the past that has to be inferred from indirect observations, or do we direct observations of solar output and ionization of molecules in highly controlled experiments?

The ionization potential for N2 is actually HIGHER than atomic nitrogen because the presence of the other nitrogen atom reduces the kinetic energy of the electrons relative to the molecule’s scattering states.

What?! Asked and answered many times with citations, the real question is why you continue to propagate crap like this: “The specific frequencies that 99% O2 and N2 absorb emit at are filtered out.” Which is false and since no instrument manufacture would say such a thing is a lie, if not by you then from where you got it from. Now you have been given citations proving it to be false I suggest you inform that source that they are incorrect and discontinue posting such misinformation.

At atmospheric temperatures, pressures, and concentrations, the IR absorption/emission by O2 and N2 are so negligible that they do not need to be incorporated into radiative transfer calculations.

In other circumstances (e.g., the planet Venus), very high concentrations can lead to some IR absorption/emission. Much of this is continuum absorption, reflecting the fact that although N2, for example, does not itself exhibit a dipole, a collision of two N2 molecules can create a temporary dipole allowing absorption. In the Earth’s atmosphere, this phenomenon is too infrequent to matter, and so for practical purposes, only the greenhouse gases such as CO2, H2O, ozone, etc., are active in IR wavelengths.

Phil, my understanding (if I am correct) is that the demonisation of CO2 as the main driver of climate is long and deep, spanning decades and probably more. Therefore siting data from large corporations and and institutions has no baring on my line of enquiry. If it did, I wouldn’t get very far before I became as confused as most people seem to be.

I think I have made my point clear enough with regard to ionisation and dipole. If you have missed something, please read it again.

So stop doing it! I’ve cited textbooks as well as commercial sources, why you would think that a manufacturer of a spectrometer would clam that there is no background IR to be subtracted from N2 & O2 if it were not so. Despite the fact that they tell you to background CO2 (water is not usually a problem because you dry the purge air as the optics are often hygroscopic).
I dislike people propagated lies about the science as you have been doing, if you stop doing so you’ll have no problems from me. N2 and O2 do not absorb IR, end of story.

Will, in the first plot, the scale in molecular extinction units shows the intensity of absorption at levels between 10^-35 and 10^-40. The absorption of CO2 in the same region is about 1. So for practical purposes, O2 doesn’t absorb IR light. It’s almost 40 orders of magnitude smaller than CO2 to an IR photon.

The second isn’t even an absorption plot you moron. It’s a scattering spectrum, which is centered at 2300 cm^-1, showing both the Stokes and Anti-Stokes wings of the Raman spectrum.

If you’re going to insist on presenting data, at least know what the hell you’re talking about before doing so.

Maxwell… You’re absolutely wrong. CO2 cannot have an absorptivity of 1 at any wavelength, not even at the band where you say it absorbs 100% of the energy emitted by the surface.

Hottel, Leckner, Modest, and more than 100 scientists and engineers have demonstrated, observationally and experimentally, that the carbon dioxide has a ridiculous absorptivity and a similarily ridiculous emissivity at the band where you say it is a blackbody.

You call me a moron but you have just helped me make my point. That is the reason for these plots.

Radiative transfer has an insignificant effect on atmospheric temperature as I have said many times above. As you point out CO2 maybe many orders of magnitude more absorptive than O2 or N2, yet this has no significant or definable effect on global temperature. Remember there is no definitive CO2 induced GW signal above normal variation, let alone an AGW CO2 signal. There is zero historical evidence showing CO2 driving global average T

If radiative transfer by CO2 was such significant factor in determining global average T, do you not think that several orders of magnitude warming effect would be quite a simple thing to demonstrate experimentally ?

Yet I have demonstrated with experiment that even with almost pure CO2 this is not the case.

In my book: http://www.spinonthat.com/CO2_files/CO2tdino.pdf which has been available as a free download since October 09, I discuss the fact that we are subsurface dwellers and that it is misleading to refer to surface warming or cooling as a greenhouse effect.

As I have said before, Phil uses to twist science based only on HIS “reliable” internet sources; you know what I mean; Phil’s is pure pseudoscience. Some posts above, he said that Te and Thb, in S-B equation , were heat. Now he’s saying that N2 and O2 are thermodynamically innert.

I’ll put it down to your lack of reading comprehension regarding the S-B terms. Regarding the absorption of CO2 , the Q-branch at ~667cm^-1 is ~1 in a 10cm pathlength cell at a volume fraction of 0.004.
For N2 the Q-branch at ~2330cm-1 in the same cell at a volume fraction of 1 is ~1.5×10^-5.
The concept that N2 and O2 do not absorb in the IR due to the lack of a dipole is shared by all physical scientists, and will be found in any text on molecular spectroscopy (e.g. Herzberg (the bible), Barrow etc.)

Eli is going to get a bit technical here, but Will is playing with a few extra cards, and we should nail this down. The interaction of molecules with electromagnetic radiation is described by a power series in the electric and magnetic fields. The strongest and first element is the electric dipole interaction, then many orders weaker (about 10^-5), the magnetic dipole interactions, then the still weaker (~10^-8) electric quadrupole, etc.

The energy of a photon that is absorbed or emitted is determined by the difference in energy between quantum states. If there is the possibility of an electric dipole (ED) transition it will dominate and the others can be ignored because they will be much weaker but not all transitions between all levels are allowed for ED transitions. For example, if in a vibrational transition the dipole moment of the molecule does not change, the transition is not allowed. This means that for homonuclear diatomic, ED transitions are forbidden.

O2, for example, has two spin unpaired electrons, e.g. a magnetic moment, and the interaction of the electron spin with the magnetic part of the electromagnetic field leads to a very weak absorption/emission which can only be measured with great difficulty, and plays no part in atmospheric physics. N2 has no unpaired electrons in the ground state, and can only interact by the still weaker electric quadrupole interaction.

CO2 has three different vibrations. The first the symmetric stretch
O[—C—]O
has zero dipole moment in all vibrational states, so there is no transitional dipole moment and it neither absorbs or emits.

The second, the asymmetric stretch starts from this position
O—C—O and moves to this one
O-C—–O . The ED does change and this transition is allowed by the ED selection rule (it is ~1900 cm-1)

The other vibration is the bend which starts from
O—C—O and changes to
C
/ \
O O

and is also ED allowed.

Now Eli, being a very sympathetic Rabett, would be overjoyed if Will stopped blathering, but he would also be surprised=:>

Fred,
Ok, let’s look at the temperature-equilibrated in the high altitude case, since I would describe it differently..
We bring in a thin layer of CO2 that contains a similar amount of CO2 compared to the whole atmosphere in a thin layer next to the top of the atmosphere.
The layer is initially already equilibrated with the adjacent atmospheric layers with respect to temperature, therefore in LTE (local thermodynamic equilibrium).
If there is no sun on the night side the radiative imbalance equals minus OLR (outgoing longwave radiation). OLR measured per unit square.
The surface and the layer cool simultaneously. The so-called “backradiation” decreases simultaneously. “Backradiation” in this case does not warm anything. It will lead to a decrease in surface cooling with respect to a reference system.
If there is sun on the day side the radiative imbalance equals Solarconstant/2 * (1- Albedo) – OLR . This is positive because of the sun. Surface and the layer heat simultaneously. The so-called “backradiation” increases simultaneously. Of course the so-called “back radiation” exists as downwelling longwave radiation, but it is not a cause for surface warming. It will lead to a decrease of surface cooling and therefore a higher temperature in the stationary state.
However, the sun is the cause or surface warming.
“Back radiation” is an effect of the interaction of the sun with greenhouse gases that describes the heat transfer from incoming solar energy via the surface to the atmosphere. One can also choose to describe the greenhouse effect without it, just looking at incoming solar heating and outgoing longwave cooling.
I’d like to add that the integrated radiative balance that you get in the 1-D energy balance models is not the physical reality, but only a way of energy book keeping. The physical reality is the instantaneous radiative balance on the day side and the night side and a rotating earth.
Best regards
Günter

I think we agree that the sun is the energy source responsible for surface and atmospheric warming.

Tbat’s the most important point. I’m still not sure what other point you are making regarding a single layer filled with CO2. Regardless of altitude, it will equilibrate at a temperature at which emissions (a function of temperature) are equal to absorption (a function of CO2 concentration), and that temperature would not be very different regardless of altitude, neglecting small changes in absorptivity and emissivity as a function of pressure. If only radiative processes are operating (which of course would not be the case in the real world), and assuming the CO2 in the layer is the only greenhouse gas in the atmosphere, the temperature would essentially be the surface temperature divided by the fourth root of 2.

In each case, the absorbed energy would be emitted equally upward and downward, and so the downwelling radiation would be similar regardless of altitude.

Correction: You forgot four possible trajectories for the energy emitted by the atmosphere. Regarding your last claim, you forgot photons streams and radiation pressure. The Second Law includes them in its contextual meanings.

I don’t believe I forgot anything, but with all due respect, you use words in a way that does not appear to apply to any real world phenomena. I don’t believe it’s unfair to state that no-one else appears to understand what you are trying to say either, despite their great familiarity with the relevant science. In any case, if you want to redo my calculations, I’ll be interested to see the results.

Do you mind if I ask you a question? On your site, you list yourself as a University Professor. What University does this refer to? Where is it located? Who are students? What courses do you teach?

John – I think if you wade through this entire thread to see the various exchanges of comments between Nasif and others, you would understand our frustration at communicating with someone who appears to be speaking a different language, scientifically speaking, from the rest of us. It also raises the question as to whether his interpretation of the meaning of University Professor differs from the ordinary one, but I hope his answer will clarify that issue. I’m not sure it’s an ad hominem attack on someone to ask him to tell us at what University he is a professor.

Regarding the greenhouse effects of CO2 as a function of altitude, I certainly remain open to any scientific explanation he has to offer, provided that I can understand it. My calculations were simply derived from the need to maintain a steady state, such that absorbed and emitted radiative flux from CO2 remain equal.

Do you mind if I ask you a question? On your site, you list yourself as a University Professor. What University does this refer to? Where is it located? Who are students? What courses do you teach?

Fred, I think this might be Nasif’s CV. It says he was appointed a “University professor” in 1974 at the Universidad Regiomontana, a university in Monterrey, Nuevo Leon, in the northeast of México having 5,000 students and three schools, Humanities, Engineering-and-Architecture, and Economics-and-Administration, and offering Master’s degrees in a wide range of subjects.

Professor Nahle held that appointment for 12 years. A year after that appointment began he founded the Biology Cabinet on the side, which he has owned and operated throughout the subsequent 35 years, during the last 24 of which he does not claim to have held any academic appointment.

Andy Warhol famously said “In the future, everyone will be world-famous for 15 minutes.” Ironically Warhol himself got vastly more than 15 minutes of fame for that bon mot. As did Nasif Nahle, who got a full 24 hours for his May 25 recognition from UA de Nuevo Leon.

This 24-hour recognition was in turn leveraged into a full professorship for Nahle at this site so as not to mislead the site’s readers into believing that Nahle was anything less than a world authority on climate science. This site quotes Nahle as follows.

“Professor Nasif Nahle of the UA de Nuevo Leon has done the ‘mean free travel’ calculations on the IR escape rate. Outgoing IR energy is delayed by at most 22 milliseconds. That is the total extent of ‘global warming’. All of the Planets CO2, the 97% from natural and the 3% from man delay temperature change by an immeasurably small amount of time. And this ‘delayed’ heat transfer is NOT radiated back to Earth. It is leaving a ‘hot’ Earth at the speed of light for a ‘cool’ outer space and is only delayed momentarily.

So if you now claim that the delay might be as much as 24 milliseconds, you are contradicting a noted authority. I would say more than 24 years, so I too am contradicting this authority, and moreover by a factor equal to the number of centimeters light travels in one second.

All this puts one in mind of Frank Baum’s H. M. Woggle-Bug, T.E.. In the case of global warming denial the microscope responsible for Woggle-bug’s H.M. (highly magnified) prefix is the climate denial machine’s urgent need for authorities equipped with the requisite superpowers to do battle with the evil Washington empire’s entrenched control over the hapless citizens of this proud nation of independent battlers for freedom from authoritarian control.

If you claim that this isn’t how that all went down, you have my full attention, at least until my plane leaves in 24 hours for India, after which I’ll be posting somewhat less often here for a couple of weeks since I have some talks to prepare. Very stupid of me to so volunteer.

Huh? Fred asked what Nahle’s academic credentials were, I simply repeated what Nahle himself writes about himself in answer to Fred’s question. I don’t see how that could be an attack on Nahle’s academic credentials, but if it was then Nahle has attacked himself in his CV.

It seems to me the desperation is on your side: you are desperate to interpret every statement about someone as an ad hominem attack even when it was not an attack on his credentials but merely what Nahle writes about himself.

What I have attacked is the statements made by Nahle, such as his 22 millisecond stuff, which is hardly the compelling argument it’s been made out to be.

Or are you so desperate to find ad hominem attacks in everything that even attacks on statements are ad hom attacks?

Interesting, Vaughan. Appointed a “University Professor” at age 23. Didn’t get his degrees until several years later. I don’t actually enjoy making fun of people just for sport, but there are reasons for informing readers of information relevant to the credibility of commentators. However, as far as I’m concerned, the “Professorship” is less important than the credibility of the comments themselves, which can easily be judged by anyone reading these exchanges.

Fred,
you wrote:
“I don’t believe there is any way to warm the surface without back radiation. In its absence, radiative imbalances in the atmosphere would change atmospheric temperature but not surface temperature (except for the minimal effects of conduction). “
I think this statement is not the correct perception of the role of the so-called “back radiation”. But I might have misinterpreted you, reading it a third time.
We agree that the sun is the only energy source. The so called “back radiation” in radiative transfer theory is the integral over all light rays in the longwave regime that reach the surface. It is an integral over angles. It is one parameter within the surface energy budget, but not the only one. Of course it cannot be omitted, but it should also not be used isolated as the physical cause for surface warming within the earth system according to my opinion. The physical cause for surface warming in the real world is the sun, as I showed in my example.
Best regards
Günter

This may seem OT, but it’s really not as we’ve been discussing downwelling radiation in regards to the general greenhouse effect, and I’d like to get some professionals to comment about the increased water vapor we’ve observed worldwide over the past few decades. This has been a long-standing prediction of AGW theory, along with increased night time temps. We know that in general the temperature is determined by dew point and cannot fall lower than that. We saw 37 new high night time temps set last summer in just the U.S. And here’s a story about more records being set in Australia during their current summer:

So, my question is: Aren’t these higher night time temps pretty much due to downwelling radiation caused by greater water vapor levels, and if they are showing a trend of increasing world-wide, at least some proof the world has been warming, regardless of the cause, but at least quite consistent with the effects expected by the primary and secondary greenhouse effects related to the 40% increase in atmospheric CO2 since the 1700’s?

A second question might be: How would C. Johnson explain these higher night time temps?

Although I have no scientific credentials whatever, my last accomplishment in that area being the Junior Trig Prize in High School in the last year of the Eisenhower administration, I felt I had to comment because when I read this thoughtful article, at the end I found “666 Responses to Slaying a greenhouse dragon” and I regard myself as a Christian — though not a fundamentalist as that term is generally understood in Academia — so I did not want to risk any evil influences on this excellent blog. The number had to be raised to at least 667.

I did not have a favorable impression of any of the Johnson papers I read, and likewise when I looked at the table of contents of Dragon I got the impression that it could easily have been a book underwritten by Joe Romm’s organization to discredit climate skepticism. Over the last few years I’ve read everything I could find on the subject, and this seemed to be almost a directory of the fringe (with exceptions, such as Dr. Ball).

Yes, yes, yes, CO2 is a greenhouse gas, which reradiates absorbed IR, particularly in the 15 micron band, half up and half down. Water vapor also reradiates in the same band, more weakly — but it is around two orders of magnitude more common in the surface atmosphere. So does O2, even more weakly but three orders of magnitude more common.

The real question is not whether the greenhouse effect exists, but rather how much net influence it has in a hideously complex and chaotic climate system, the overall effect of which is to transport unimaginably huge quantities of heat and moisture from point A to point B.

The “consensus” types are fond of citing Arrhenius. Well, back in 8th Grade Science, between contests to see who could get the girl with the long ponytail to stand next to the vandeGraaf generator, we learned about the greenhouse effect: yep, it raised temperatures around 30 deg C, but it actually should have raised them by around 60 deg C according to calculations. “Settled science.” So although the greenhouse effect is quite real, it would appear that other processes (feedbacks?) reduce the effect by about half. Interestingly, if one takes the “consensus” figure of 1.2 deg C sensitivity for CO2 doubling and applies 50% negative feedback to it, one gets a sensitivity around half a degree, which is in the same general range as the conclusions of such distinguished researchers as Lindzen and Spencer.

So that’s reason 1 for my skepticism. Reason 2 is that basic physics tells us that at the pressure of a standard surface atmosphere, CO2 relaxation by bonking into other molecules is several orders of magnitude more probable than by emission of yet another errant photon. This means its “activation” by IR absorption is almost instantly thermalized, which will cause it to participate in convection, which will lift it eventually to the convective boundary layer where lower pressure will make pinging a photon into outer space much easier. But if convection, rather than radiation, is the dominant mode of heat transfer in the lower atmosphere, where storms, precipitation, and suchlike horribles are generated, how could CO2 changes affect the weather? After all, hundred-year events are so-called because, although they are rare, they do occur — CO2 concentration be damned. Witness the ’67 Chicago blizzard or the mid-70s floods in Australia and Pakistan.

Reason 3 is that in spite of careful reading of such sources as your Ch. 13 [IIRC] and ScienceofDoom, it is still unclear to me how changes in incident IR can have a measurable effect on ocean temperatures, 70% of the surface area of the planet and close to 100% of its thermal capacity. IR apparently penetrates no more than a few microns into water; the next several millimeters are cooled by evaporation; and the next hundred meters or so are effected principally by incident visible and UV, with the relative UV content determining how deep the effect penetrates. Sure, the top bit is sloshing around constantly with wind and waves, but a few microns?? In a mixing layer hundreds of meters deep???

And reason 4 is that in the many peer-reviewed climate papers I’ve read over the last few years, the overwhelming majority were like the excellent and interesting paper of yours I read from a link here a month or so ago, dealing with the relation between sea surface temperature, atmospheric pressure, and tropical cyclone wind force [IIRC]. It struck me (again, a layman) as an interesting and useful piece of research, doubtless to be cited as fundamental in future storm studies. (Not to mention the impressive and expensive full-color graphs. Do de name Arlo Guthrie ring a bell?) But as to IPCC-style climate alarmism, it simply offered a neat one-paragraph professional curtsy to CO2 and climate change — enough to satisfy the “climate change” section of the grant application, but no more. This is fine and understandable in the current political climate, but it amounts to a demonstration that when we hear the claim that billions and billions of scientists agree with the CO2-driven catastrophic global warming theory, it’s time to hold on to our wallets.

Craig – You have clearly thought about this issue and so you deserve a response. Perhaps not a long one here, however, because the thread is devoted to something else, and more importantly, because all the points you mention have been discussed in detail elsewhere. Briefly, however, the most likely value of climate sensitivity is estimated to be about 3 C for doubled CO2. This takes into account convective heat transport – without convection, the value would be much higher.

Regarding ocean heat storage, downwelling IR contributes substantially more than solar irradiation. Essentially all IR reaching the ocean surface is absorbed within the “skin layer”, and the heat is distributed throughout the entire mixed layer (down to as much as 200 meters) by turbulence and convective mixing, so that solar and infrared contributions are homogenized.

It may be unfair to ask you to wade through previous threads, but if you are willing, you will find these phenomena addressed extensively.

For now I’ll take Craig’s side on this over Fred’s. Fred can redeem himself by defining the problematic notion of “climate sensitivity.” Go for it, Fred. The previous threads you cite as having addressed “these phenomena” extensively don’t seem to have addressed that particular notion. Given the central role this concept plays in the conventional wisdom about global warming, this strikes me as an egregious oversight.

Thanks, Fred, but I have read (or, in certain cases of extreme exhaustion, at least skimmed) all of the relevant threads on this blog since its inception. The 1.2 deg C figure I cited was, I thought, even the IPCC’s basic CO2 sensitivity figure, theoretical, in the absence of feedbacks. If I’m mistaken, please provide a page reference in AR4. Otherwise I stand by all of my assertions above.

The term “skin layer” is used both to refer to the microns-thick IR absorbing layer and the millimeters-thick layer cooled by evaporation; in which sense are you using the term? This is the same ambiguity I find in nearly all attempts to describe the IR effect in the ocean — even Dr. C’s, otherwise a model of explicitness and clarity. If you mean the mm layer, it’s possible but the layer is by all accounts cooler; if you mean the micron layer, the difference in scale and near-certainty of evaporation makes it simply unbelievable, no matter how strong the wind or high the waves (I’m an avid amateur sailor). Not to mention that given the relative heat capacities of the atmosphere and the ocean, the idea that any atmospheric phenomenon could have a perceptible effect on ocean temperatures is implausible, to say the least — the “mixing layer” of the ocean alone — defined as you do — having two orders of magnitude more capacity than the entire planetary atmosphere.

I regard the publication of Dragon at this point in time as particularly unfortunate, since the always-improbable and faintly ridiculous CO2-driven AGW theory has managed over the last two decades to get taxpayers worldwide to spend more than $100 billion researching itself, only to have all actual relevant measurements produced by this research provide counterevidence. There is no need for silly fringe attempts to “debunk” it. But you are quite right; if this is not off-topic, it is at least pushing the very edge.

Estimated climate sensitivity with feedbacks is about 3 C per doubling. Without feedbacks, it’s 1.2 C. The IR downwelling radiation contributes considerably more to ocean heating than solar radiation. Both are mixed into the mixed layer, and each contributes proportionately to evaporation, which is why the temperature of the skin layer as measured by satellite is slightly cooler than the water immediately below. If the IR contributed disproportionately, it would be hotter, and that would be observed in the satellite data.

This NASA file shows the shallow upward thermal gradient from convection, but also that the skin layer is cooler than at 10 um and only slightly warmer than at 1 meter – Ocean Temperature . For IR absorption to be disproportionately dissipated into evaporation rather than heating would require a far greater difference between the surface and the 1 meter depth, given the relationship between temperature and evaporation rate. In essence, solar and downwelling IR are combined so that they contribute in proportion to heating and evaporation.